Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Archives of favorite topics => Topic started by: Willabe on December 08, 2015, 03:55:44 pm
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I thought I'd break this of from a thread so as not to hi-jack it.
HBP posted a link to a interesting electronics Hi-Fi(?) magazine on testing for distortion in caps.
http://www.scribd.com/doc/2610442/Capacitor-Sound (http://www.scribd.com/doc/2610442/Capacitor-Sound)
I read it and asked HBP if he would care to boil it down a little. His response;
"If a cap was an ideal device and introduced zero distortion, it would have no "sound" and all caps with identical ratings would be interchangeable.
Except that almost all caps measured had at least some distortion, which seemed to follow these rules:
- The bigger the cap, the less distortion (relates to different dielectrics and construction styles), except
- Sometimes caps of a specific dielectric distort much more/less than other of the same dielectric (ceramic was notable when 2 different types exhibited the most, and almost the least, distortion of all caps tested
- Bias (voltage) across the cap increases its measured distortion (which is bad because we use caps specifically in places where there will be d.c. across them)
- Higher voltage caps seem to exhibit less distortion than lower voltage caps of the same type (which also amounts to them being bigger), and
- The rules don't always hold up (and there are bad apples even among normally-good types) so you should measure the specific caps you want to use to see how they really perform."
So if you hear a sound change when swapping caps, you're really hearing the difference in the artifacts each cap overlays on the intended signal."
Then Jojokeo asked;
"Great breakdown of the info HBP. Thank you.
But (sorry can't read it now) does it mention anything regarding caps "breaking in" or becoming accustomed to certain voltages being placed on them to where the dielectrics sort of "form" or "settle-in" similar to e-lytics?
2nd - Does it mention anything regarding outside foil direction/placement and the related characteristics or phenomena this may have?"
Here's some from my Bread Board thread on my testing different caps for tone;
Even though this is a BB, I wanted to change the K bypass cap and the plate coupling cap (CC) very fast to really hear the difference in real time and not from my ear's memory. I want to take out any second guessing.
To me this was very important especially for the CC's. I bought several different brands to see IF/how much different they might sound.
So, for the 1st preamp gain stage, I made up a couple of brackets from some parts I had laying around to mount a couple of rotary switches. They both are movable so I can use them on other gain stages too. I did test and mark the outside foil on the CC's. (They don't look real pretty but they work fine.)
For the K bypass caps I used a 2P6T rotary set up like this;
Position's;
1. Open/No bypass cap.
2. 0.68uF.
3. 2.2uF.
4. 4.7uF.
5. 10uF.
6. 26uF.
For the plate CC I used a 1P8T rotary (I had this here, bought it from Weber years ago, BIG honkin rotary ) I measured each cap for capacitance and I went through the Mallory 150's I had on hand and found a yellow (old) and white (new) that were both 22.02nF. All the other cap brands I had at lest 2 each and measured for the closest to 22.00nF. Rotary switch set up like this;
Position's;
1. Mallory 150/white/630v/22.02nF.
2. Mallory 150/yellow/630v/22.02nF.
3. Jupiter/yellow/600v/20.39nF.
4. Jupiter/red/600v/19.28nF.
5. SoZo/blue/400v/22.02nF.
6. Musicap/600v/23.00nF.
7. AuriCap XO/600v/20.78
8. Mojo Mustard/630v/22.05nF.
I didn't have room for the OD 225 and 715. I also don't have a SoZo mustard, I'll test those later.
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And;
"Well, I changed out that coupling cap (CC) 1P8T rotary switch (RS) that was giving me problems with the new Alpha 1P12T RS, it's working GREAT! Very smooth and very fast. Play something and reach with my left hand for the switch and then play the same thing, very easy to hear any change in tone. (http://el34world.com/Forum/Smileys/default/icon_biggrin.gif)
I also added the 2 OD caps I had, 1@ 715/400v, 1@ 225/400v.
I played another hour or so and I am hearing some differences BUT NOTHING where I can say this cap is the best hands down.
Tests were done with the set up in reply #93, I had my Fender stand alone Reverb feeding the Champ 5F1 (with a Fender single knob tone control engaged). All test's this round were with the volume set at ~11:00, tone set at ~2:00, no change in those settings;
1. One of the differences I'm hearing is the overall frequency response across the full frequency spectrum. Some had less bottom bass end, so they sounded more bright. BUT at the same time, the brighter caps had less bottom end distortion.
2. Second difference I'm hearing is depth/3D sound. Some sound more flat/lifeless, not frequency so much but depth, more like adding a slight amount of reverb.
3. The 3rd thing I'm hearing is some seem to sound better with single notes and some seem to sound better with cords when left to sustain/ring out. There's a smoother sustained 'grind' and a very nice 'swirl' that sounds real good to me. Sounds like a big amp, Marshall/HiWatt, that's not over the top with a fuzz before it or on 10. Real nice for some things.
I only did all these test with only 1 guitar so far (re-issue 80's rosewood fret board Strat, stock PUPs, neck PUP, volume/tone full up).
As I said this is with 1 guitar/PUP's and no change in the amps/guitars volume/tone controls.
So...... so far I think that for the same reasons that I might reject some of the caps, I believe others would love those same caps. (http://el34world.com/Forum/Smileys/default/dontknow.gif) "
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And;
"Here's the caps I tried, uF value tested before soldering them up to an Alpha 1P12T rotary switch so I could compair them instantly and not from ear memory;
1. Mallory 150/white/630v/22.02nF.
2. Mallory 150/yellow/630v/22.02nF.
3. Jupiter/yellow/600v/20.39nF.
4. Jupiter/red/600v/19.28nF.
5. SoZo/blue/400v/22.02nF.
6. Musicap/600v/23.00nF.
7. AuriCap XO/600v/20.78
8. Mojo Mustard/630v/22.05nF.
9. Orange Drop/400v/22.74nF.
10. OD 715/400v/22.30nF
Here's what I think so far after 3 different rounds of playing on 3 different days, playing single notes and full chords, both with -FB and without -FB;
1st, I think ALL the caps would definitely work fine for different people, in different builds, with different guitars, different PUP's and different music/playing styles. (Remember I'm testing these caps in a SE Champ, 5F1, 1x6V6, V1a/b ~150dcv plate, 6V6 ~360dcv and the 12T CC rotary switch is connected to the 1st CC from V1a plate to V1b volume control, with a Strat. And I only tested 1 of each as a sample.)
Also, and I don't know what it means, was when I tested for the caps outside foil lead, some were way noisier than others. (I mean how noisy the cap is with the outside foil lead hooked up to the test amps input.) The Mallory's were the nosiest with the white being the worst. The Musicap and AuriCap were by far the quietest. The quite 1's had very little difference in noise when flipping the switch to flip the caps leads. And on the outside foil cap lead to the test amps input they were way quieter than the other caps on their outside foil lead. Big difference.
I was thinking, before these tests, that the fatter the cap the more shielding it would have from outside foil lead to the inside foil lead. So larger values/larger voltage rating(fatter cap) would have more difference when switching leads. A 0.1uF cap is way easier to hear a difference than a .0047uF cap, I have a very hard time hearing any difference in leads on a Mallory white 150. (I know that Tubenit and Gezzer have posted they hear the opposite. (http://el34world.com/Forum/Smileys/default/dontknow.gif) ) But the Musicap was the quietest and is the thinnest.
So far, for the sound I'm wanting, my least liked sounding cap (to me) is the white Mallory 150. Flat , no/not much depth(3D depth) and thinner/less bottom end, yet clean(er) sounding and a little more forward/aggressive sounding? And the yellow Mallory's 150 sounds different than the white. It's fuller and has some better depth to it. But is not as clean on the bottom, because it has more bottom extended range?
(I noticed that the shape and size/dimensions changed on the 22nF 150's but not on the other values I have of the 150's. The yellows are just a little shorter and fatter. I'm gonna have to try a few other white/yellow 150 values and see if they sound closer to the same rather than different on the bottom end.)
(I have a couple of old Fender blue tubular caps from the BF amps around here somewhere. I'll see if I can find them then test them to make sure there not leaking any dcv. Might be a good base line?)
The Musicap was/is the most balanced to my ear, top/middle/bottom end, very nice sounding, maybe the nicest mid range, had the most 3D depth of sound, smoothest distortion and had the best ringing sustain smooth growl/swrill on a full cord left to ring out. I think it has/lets the most harmonics through? It's also, unfortunately, the most expensive.
AuriCap was very good too, although a little cleaner/less bottom end but clearer because of it?
The blue SoZo, another pricey(er) cap, sounded pretty thin to me and pretty flat sounding too. But again very clean/clear sounding. (Might sound great with a big Jazz box guitar?)
The Jupiters sounded good, pricey(er) caps, the yellow sounds pretty good, fuller and some/more depth than most. But the red costs more than the yellow, red has a tube/sleeve it's in and they sound close but less bottom and cleaner/clearer.
I can hear why Tubenit likes the OD 225's. They sound more like/close to the yellow 150 and yellow Jupiter caps. Fuller bottom, more depth, nice mids, a little less bottom that the yellow 150 and yellow Jupiter. (Might be that the mids are a little more apparent because there's a little less low end?) The OD 715 is cleaner and brighter with less bottom end distortion. For a cleaner amp, maybe for a Jazz player with a big body git box, they might sound very good?
Mojo Mustard was good, maybe a good in between cap from a bright to bassy(er) cap? I like it."
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And;
"I just was playing for ~hour or so with the same set up as noted before. I don't know why but some days I hear a bigger difference then other days. And the differences are definitely more pronounced on some days. (http://el34world.com/Forum/Smileys/default/dontknow.gif)
I've been thinking about this and I thought maybe it has to do with the Champs volume/single tone knob settings?
Not how loud dB wise, I can hear the amp/speaker just fine volume wise.
But I'm thinking that distortion is having an effect in hearing any differences in the different caps? I'm going to go with the word artifacts because there are extra bits/harmonics I'm hearing? I'm wondering if you have to push the cap enough to make these artifacts heard? Going past the caps linear range? That's when I hear them more clearly? I'm going to move the CC rotary switch to V1b's CC and see if that position in the circuit pushes the CC's a little more? (http://el34world.com/Forum/Smileys/default/dontknow.gif)
Also if having V1b's K bypass cap, 10uF, in or out, I have it on a 1P1T switch.
So I tried it at different volumes and different tone settings with V1b's K bypass cap in and out. It did make more of a difference.
I'm hearing the most difference, most artifacts, on the B/G/D/A strings with the amps volume up ~50% and the tone control up to ~2:00 with V1b's K bypass cap in the circuit. Cords and double stops on those strings are the easiest to hear the differences/artifacts/the extra bits/harmonics?
There's a 'grind' and a 'depth' on cords and double stops on these strings and settings that I'm hearing. It's more pronounced with some caps then others AND I hear it in different parts of the frequency range."
"I also added 3 new caps to the 1P12T rotary switch that changes the coupling caps going from V1a to V1b.
I bought them from Angela Instruments ~ $14 each. Their Fender brand caps, 660v/5%;
Red; measured; 21.48nF; Kraft paper/Tin foil/Resin. (Red Astron/early tweeds) Sounded the fattest/warmest/full range break up.
Yellow; measured; 20.22nF; KP/Tin/Wax. (Yellow Astron/late tweeds/some brown face amps) Sounded not as fat but had the most 'hair' in the upper mid to treble. Pronounced picking attack, clicky sounding.
Blue; measured; 22.22nF; Mylar/Tin/Wax (Blue Astron/BF amps) Sounded the brightest and cleanest, least amount of 'hair'."
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HBP, Thanks for your answer but do you see any link between what I'm hearing and the 2nd and 3rd harmonic distortion in the authors test's?
That's what I was looking for in it.
He also talked a little bit a few times about inter modulation distortion. How is that different in what I'm hearing than 2nd/3rd harmonic distortion? :dontknow:
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HBP, Thanks for your answer but do you see any link between what I'm hearing and the 2nd and 3rd harmonic distortion in the authors test's?
2nd, 3rd and sometimes many higher-order harmonics...
Investigate the Harmonic Series (https://en.wikipedia.org/wiki/Harmonic_series_(music)). Compared to a tone, the 2nd harmonic is an octave higher, the 4th harmonic is 2 octaves higher, the 6th harmonic is 2 octaves and a fifth higher, and the 8th harmonic is 3 octaves higher. All of these are fairly consonant with the original tone and explain why lower-order even harmonics are considered benign.
For the odd harmonics, the 3rd harmonic is an octave and a fifth, the 5th harmonic is an octave and a major 3rd, the 7th harmonic is 2 octaves and an out-of-tune flat-7th, and the 9th harmonic is 3 octaves and a 2nd (or 2 octaves & a 9th, however you prefer to look at it). Odd order harmonics (and all higher-order harmonics) are generally considered to add "bite" to a sound, and in large amounts could sound "grating".
As for your results: all caps you tested except the Musicap, Auricap and OD 715 are polyester dielectric; the caps I mentioned are polypropylene dielectric, with the expectation they'd perform better (sound cleaner in this case).
As for results? We'd expect any cap that sounded "warm" to have more even harmonic distortion and/or distortion products that skew towards the lower-order harmonics being louder. We'd expect that caps that sounded "bright" to either have more odd harmonic distortion (than even), higher-order harmonics, or even a cleaner sound that didn't have excessive low-order distortion. However, we can't know any of these guesses are correct without duplicating the article author's test rig, but adding a bias voltage for testing that simulates the preceding tube's plate voltage. The author didn't test with bias voltages greater than 100v because he was using a bunch of batteries as his source of d.c. voltage (to eliminate that as a variable).
He also talked a little bit a few times about inter modulation distortion. How is that different in what I'm hearing than 2nd/3rd harmonic distortion?
Harmonic distortion is musically related to the original single tone, and is always a higher frequency.
Intermodulation is when two tones are passed through a non-linear impedance (often a distorting active stage, like a tube); the output of the non-linear medium is made up of the two original tones, plus 2 new frequencies: the mathematical sum and difference of the two frequencies. So 100Hz and 1kHz would have IM products of 900Hz, 1.1kHz, as well as the original tones of 100Hz and 1kHz. The new tones are almost guaranteed to not be musically related to the original tones. Also, IM can be a source of subharmonics below the original notes, since one of the products is the difference between the tones.
Not only do the 2 original tones create 2 new tones, but any distortion of the original tone also interacts with the tones passed through the nonlinear impedance. Things become a mess real fast.
You may not have noticed, but the author used 1kHz for the bulk of distortion testing, then switch to 100Hz and 1kHz for IM testing, but still displayed only frequencies above 1kHz for his distortion plots. When there was THD of the single 1kHz tone, you saw peaks at 2kHz (2nd harmonic), 3kHz (3rd harmonic), 4kHz, 5kHz, 6kHz, etc. When he did IM testing, IM distortion showed up mostly as "pickets" 100hZ to either side of a harmonic distortion frequency. So there was a little peak at 1.9kHz and 2.1kHz (IM centered around the 2nd harmonic, with 100Hz sum/difference frequencies), 2.9kHz and 3.1kHz (IM centered around the 3rd harmonic), etc.
So IM distortion is always considered to be the greatest evil, because all sorts of non-musical trash winds up in your sound.
We can guess that "clean sound" could be a lack of distortion, or that "edgy/biting sound" could be odd-order or IM distortion, but we really don't know without doing some testing. And note the author was trying to use statistically-relevant sample sizes in his tests (like running all tests, under all conditions, on 20-30 caps of a single brand/type to verify the results were a bad cap or bad batch).
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Eventually I'll get my test-cap rig completed and do some listening myself.
So far the candidate caps are as follows:
- Mallory (CDE) M150 (metalized polyester)
- Fender Red (Kraft paper/Tin foil/Wax)
- CDE 418P (polyester film/foil; successor to OD 225P)
- Solen MKP-FC/PPM (metalized polypropylene)
- Auricap XO (metalized polypropylene)
- CDE 715P (polypropylene film/foil)
- Musicap (polypropylene film/foil)
- K42Y-2 (small green paper in oil)
- K40Y-9 (larger silver paper in oil)
- K75-12 (hybrid paper/PET (polyester) in oil)
- KSG-2 (Mica) or SSG-1 (mica)
- FT-2 (Teflon) or FT-3 (Teflon)
Where there's an "or" it's because some types don't offer certain values, and a substitution for the closest type with the specified dielectric/construction was made.
Everything after the Musicap is a Russian cap type. I'm mounting these thing inside a former GR decade resistor box, and the mica & teflon caps are rather huge & heavy. So I'll have to secure those to the box itselfas the switch alone can't support them. Even some of the oil types are quite heavy for their size... So that's slowing assembly down a bit.
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So I tried it at different volumes and different tone settings with V1b's K bypass cap in and out. It did make more of a difference.
I'm hearing the most difference, most artifacts, on the B/G/D/A strings with the amps volume up ~50% and the tone control up to ~2:00 with V1b's K bypass cap in the circuit. Cords and double stops on those strings are the easiest to hear the differences/artifacts/the extra bits/harmonics?
This seems to jive with what the author wrote. Higher signal levels resulted in more distortion in his tests, for caps that distorted. That seems to correspond with you having the cathode bypass cap engaged, because that's higher signal level at the plate output.
Noticing differences with cords/doublestops is probably both cap distortion and/or IM products being more noticeable.
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Brad and Brian,
When this thread is done .......... can one of you edit it and place it into ARCHIVES. Good info here.
With respect, Tubenit
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HBP - in your summary, did "bigger" mean physical size, voltage rating, uF???
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Great thead!
@DMP: for caps, bigger in voltage, or uF, basically means bigger in size. Caps are analog devices. Note: this is true within cap types. E.g., a ceramic cap of a certain value may be smaller than a poly cap of that value. But at some point a larger value ceramic cap must be physically bigger than a smaller value ceramic cap, etc., etc.
@ all: to get a verifiable tone comparison would require double blind tests, preferably taken over several sessions, and using multiple participants.
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@ all: to get a verifiable tone comparison would require double blind tests, preferably taken over several sessions, and using multiple participants.
I agree, come on over. :icon_biggrin:
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Brad and Brian,
When this thread is done .......... can one of you edit it and place it into ARCHIVES. Good info here.
+1 very cool of you guys to do this and post such detailed info. At some point, even though you listed the caps very well, could you post photos of the caps please? Thinking this will also help a lot since our memories are "picture generated" i.e. photographic and also to help verify things and help eliminate possible confusion?
ps - I'm surprised with your results of the yellow vs white Mallory 150s. I thought these were supposed to be the same when they only supposedly changed colors a few years ago?
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I'm not sure on that, it may be just that .02 value?
I have a lot of different values of the yellow and white Mallory 150's and they all are the same size except for the .02 value. It might just be that value or a bad apple?
I have not tried multiple samples of the same cap. :dontknow:
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Brad and Brian,
When this thread is done .......... can one of you edit it and place it into ARCHIVES.
Sure we can do that. :icon_biggrin:
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And;
"I just was playing for ~hour or so with the same set up as noted before. I don't know why but some days I hear a bigger difference then other days. And the differences are definitely more pronounced on some days. (http://el34world.com/Forum/Smileys/default/dontknow.gif)
I've been thinking about this and I thought maybe it has to do with the Champs volume/single tone knob settings?
@ all: to get a verifiable tone comparison would require double blind tests, preferably taken over several sessions, and using multiple participants.
I agree, come on over. :icon_biggrin:
Ok, where are you!?!
Maybe a spouse, friend, bandmate whatever could work the rotary SW, and keep a record of that; while you keep a record of your tonal impressions. No peeking or cross-talk between the SW operator and the listener. Double blinding is a big project, but might be worth it considering how much work you're doing anyway.
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I've been asked to stop in.
I'm quite agnostic about cap "sound". Most good caps sound the same to me. Certainly so now that I have lost much hearing.
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I've been asked to stop in.
I'm quite agnostic about cap "sound". Most good caps sound the same to me. Certainly so now that I have lost much hearing.
You and me both brother.
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This is a very good test database Willabe!
I didn't have the chance to test as much not even on guitars which are my real field of operation, and I don't have that many different types of caps to do so, only thing that I've tried is different values which does really change the depth of the tone control. On guitars I haven't noticed any difference with different types of caps.
Now on amps, that is a completely different field. Some caps may not have any audible difference but some might be noticeable right the way as you have tested.
Here a interesting video of the same sort of test on a guitar tone control:
https://www.youtube.com/watch?v=92G-jw4TqS4 (https://www.youtube.com/watch?v=92G-jw4TqS4)
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HBP - in your summary, did "bigger" mean physical size, voltage rating, uF???
Yes. :l2:
You need to understand something about how capacitance (https://en.wikipedia.org/wiki/Capacitance) works. In general, a cap's capacitance goes up when the plates of the cap are moved closer together, or if the area of the plates (and their overlap) is made larger. There's also a fudge factor which accounts for the insulator between the plates; different insulators generally increase the capacitance of a given capacitor compared to using air (space between the plates) as the insulator.
But every insulator has a breakdown voltage; if you need a higher voltage rating with a given insulating material, you might need more of it between the plates, and then make the plates larger. So the cap gets bigger 2 ways there.
There's a battle between ideal insulating material and how huge a cap of a given Farad-rating gets with that insulator. You're not gonna see caps above 10's- to maybe 100-pF which are insulated by air between the plates. If you put a good piece of plastic between the plates, you can move them much closer together for the same voltage rating. Except now maybe that plastic absorbs more electrons than plain air. Capacitance went up for a given size and/or the size got much smaller for a given capacitance & voltage rating.
I mention all this because the author's tests generally note lesser distortion for higher-voltage-rated caps (IIRC). But then he also noted less distortion for film/foil type caps than for metallized caps with the same dielectric.
You can roll up a cap with alternating pieces of aluminum foil & polyester. The mating surfaces of the materials won't be in perfect contact everywhere, so the resulting cap is bigger than it might otherwise be. Metallization is sputtering vaporized metal onto a plastic film to form a conductive surface (which the author notes is still thin enough to see through). Doing this, you dramatically decrease the size of the cap for the same value, voltage rating & dielectric. Note how a metallized polyester Mallory 150 is much smaller than a film & foil polyester orange drop 225P/418P.
Except that C0G ceramic caps don't seem to be huge for a given rating, and they had almost the lowest distortion of any cap tested (but other general-purpose and lower quality cermaics like the X7R were absolutely horrible).
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Here a interesting video of the same sort of test on a guitar tone control:
I watched his 2 videos and didn't like the test approach.
He starts off intending to test different dielectrics, but all caps except one are polyester. There are, however, construction difference which relate to the size of the caps. Of course changing the value of capacitance changes the action of the tone control.
But a tone control is a lousy place to reveal the sound of a cap (signal is just being eliminated). Also, the pickup is a coil with inductance, and we're introducing a series cap in the circuit. If there are small differences in each cap's actual capacitance, this will change the sound of the pickup and the inductance resonates with the changed capacitance a little differently than the previous cap, which changes the pickup's sound. So there are explainable reasons for tonal changes if everything is not otherwise identical.
All that said, I'm not shooting for perfectly identical capacitances in my test setup, mainly because I can't afford to buy many of each cap type to get exactly-matching capacitance values. Also, some caps (due to dielectric material and size) only came in certain value and/or voltage ratings, meaning I have to put caps in series or parallel to get the right composite cap value/rating. And I had cases where 0.05uF was available for a certain cap type, but the 0.047uF value of other types cannot be exactly duplicated. Etc, etc.
But in the end, I'll probably listen to the caps taking the place of a coupling cap in a simple Valve Jr circuit (but through much better speakers than the on-board Eminence). Either I'll hear a "Wow!!" difference or not, and it should be pretty easy to account for a tiny bit more bass in a 0.05uF cap over a 0.047uF cap (if it's even audible).
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a tone control is a lousy place to reveal the sound of a cap (signal is just being eliminated).
I agree about his approach not been the best, it doesn't change the tone while spinning the tone control, just the depth of the tone as the value changes. I understand in amps it will do make a lot more difference.
....... bit more bass in a 0.05uF cap over a 0.047uF cap (if it's even audible).
Oh I did like this note about more bass, I don't like too bright sound, so if those initial input caps in an amp are swapped for lets say, .056 or .06 or .068 so there will be a little more bass, which caps would be key in setting the overall tone in an tube amp?
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Willabe and HBP,
I'd love a best guess on this........ Do you think IF I replace 4 of these caps with Musicaps that there would likely be a noticeable to significant difference in tone on the clean channel?
My guess is it will.
Ken Fisher years back suggested to change just the 2 blue molded coupling caps to PP caps for the PI in BF amps. Gerald Weber picked up on it and many of the amps he built to sell had Malory 150's for the pre and PP's for the PI.
I have a Champ 5F1 set up on the BB to do my cap testing, so only 2 coupling caps. I have the 12T rotary switch set up for the 1st coupling cap going from V1a to V1b.
I'm going to add a 2nd 12T rotary switch for the 2nd coupling cap, going from V1b to the 6V6, and see if it makes a bigger, more noticeable change in tone. I'm thinking it will.
I need to go down in my basement and find a couple more of the brackets I used for the rotary switch. I've already bought a few more of the caps I need to do this.
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Maybe a spouse, friend, bandmate whatever could work the rotary SW, and keep a record of that; while you keep a record of your tonal impressions. No peeking or cross-talk between the SW operator and the listener. Double blinding is a big project, but might be worth it considering how much work you're doing anyway.
I'm trying to get 3 of the guitar players from church together to do this. But 1's studying for his collage finials and the other 2 have families/young kids. So, it will be a while.
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I'd love a best guess on this. This 5879 OD version of my D'Mars has mostly Orange Drop PS series. Forget the OD channel for a minute and think of this as just the clean channel into the LTPI and power amp.
Do you think IF I replace 4 of these caps with Musicaps that there would likely be a noticeable to significant difference in tone on the clean channel?
I have no idea. :dontknow:
That's why I'm building the box the way I am: Selector switch which sets 0.022uF, 0.047uF or 0.1uF as the active range being used, then 12-pole switch for that range to pick which of the caps I listed as the in-circuit cap. Then listen to see how it sounds.
Maybe the cap has a sound, maybe it doesn't (I'm building what I am to hear for myself). Notice Willabe said, "I played another hour or so and I am hearing some differences BUT NOTHING where I can say this cap is the best hands down." Any difference might be very small. Maybe a cap type has an impact one place in the circuit but not in another. For me it's too expensive to buy some of these and not know whether the cost is justified. Also, some types are physically HUGE (see below) and require advance planning to use, as well as being expensive; it seems prudent to know up-front whether they're worth the trouble & expense.
... At some point, even though you listed the caps very well, could you post photos of the caps please? ...
Ask and ye might receive... :icon_biggrin:
Caps below are left-to-right in the order I noted in my earlier post (http://el34world.com/Forum/index.php?topic=19534.msg202811#msg202811).
Maybe a spouse, friend, bandmate whatever could work the rotary SW, and keep a record of that; while you keep a record of your tonal impressions. No peeking or cross-talk between the SW operator and the listener. Double blinding is a big project, but might be worth it considering how much work you're doing anyway.
Agreed double-blind is the way to go. Then again, so is playing a pre-recorded passage through the amp to rule out playing variations. I doubt I'll be able to arrange such, and will have to consider "wanting to hear a difference" in the results.
"What I'd like to hear" from testing: large, clear differences between caps to justify selecting one over another in an amp.
"What I expect to hear" from testing: A difference, if any, that's slight and could be overwhelmed by a tone control setting change.
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Except that C0G ceramic caps don't seem to be huge for a given rating, and they had almost the lowest distortion of any cap tested (but other general-purpose and lower quality cermaics like the X7R were absolutely horrible).
Ok, how do we know which is which if/when we buy some? And are silver mica caps a 3rd type?
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it doesn't change the tone while spinning the tone control, just the depth of the tone as the value changes.
Well yes it does, it rolls off the hi end. Changing values is a different thing.
Oh I did like this note about more bass, I don't like too bright sound, so if those initial input caps in an amp are swapped for lets say, .056 or .06 or .068 so there will be a little more bass, which caps would be key in setting the overall tone in an tube amp?
Any of the coupling caps, maybe you might hear more of a difference changing the 1st coupling cap. :dontknow:
As far as going from .056 to .06 or .068 using the same brand/type of cap that's not much of a change.
Either I'll hear a "Wow!!" difference or not, and it should be pretty easy to account for a tiny bit more bass in a 0.05uF cap over a 0.047uF cap (if it's even audible).
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But a tone control is a lousy place to reveal the sound of a cap (signal is just being eliminated). Also, the pickup is a coil with inductance, and we're introducing a series cap in the circuit. If there are small differences in each cap's actual capacitance, this will change the sound of the pickup and the inductance resonates with the changed capacitance a little differently than the previous cap, which changes the pickup's sound. So there are explainable reasons for tonal changes if everything is not otherwise identical.
Ken Fisher used this to back saying that changing the tone cap in a guitar will change the tone. Said it was like how a wha wha pedal works. He went as far as to say certain caps won't let you roll off the tone to get 'women tone' like Clapton or Lesli West.
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Except that C0G ceramic caps don't seem to be huge for a given rating, and they had almost the lowest distortion of any cap tested (but other general-purpose and lower quality cermaics like the X7R were absolutely horrible).
Ok, how do we know which is which if/when we buy some?
Buy them from a reputable seller which identifies the type (and/or temperature coefficient, often +/-30ppm for C0G). Look at a cap data sheet (http://www.mouser.com/ds/2/212/F3101_GoldMax-334604.pdf) and know the markings for that brand which indicates C0G (which might mean looking for tolerance, as it seems only C0G caps are rated for very tight tolerances of 5% and less).
And are silver mica caps a 3rd type?
Yep, mica is not ceramic.
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Ken Fisher used this to back saying that changing the tone cap in a guitar will change the tone. Said it was like how a wha wha pedal works. He went as far as to say certain caps won't let you roll off the tone to get 'women tone' like Clapton or Lesli West.
Listen for yourself, just changing the cap values and not type.
https://www.youtube.com/watch?v=8t_eqST1pWQ (https://www.youtube.com/watch?v=8t_eqST1pWQ)
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Sorry, I should have been clearer, he (Fisher) was talking about type/brand not value.
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Maybe the cap has a sound, maybe it doesn't (I'm building what I am to hear for myself). Notice Willabe said, "I played another hour or so and I am hearing some differences BUT NOTHING where I can say this cap is the best hands down." Any difference might be very small. Maybe a cap type has an impact one place in the circuit but not in another. For me it's too expensive to buy some of these and not know whether the cost is justified. Also, some types are physically HUGE (see below) and require advance planning to use, as well as being expensive; it seems prudent to know up-front whether they're worth the trouble & expense.
Agreed double-blind is the way to go. Then again, so is playing a pre-recorded passage through the amp to rule out playing variations. I doubt I'll be able to arrange such, and will have to consider "wanting to hear a difference" in the results.
"What I'd like to hear" from testing: large, clear differences between caps to justify selecting one over another in an amp.
"What I expect to hear" from testing: A difference, if any, that's slight and could be overwhelmed by a tone control setting change.
I found this to be true to some extent. Re- adjusting the controls for each cap especially the tone knob did alter/nullify any differences between the caps, some more than others. That's why I left the volume and amps single tone control (5E3) set the same for all tests.
But, I still think some caps were warmer sounding and had more of a 3d depth, this was harder to change by adjusting the volume and tone control. Some if not most of these artifacts/differences in tone still stayed.
Also I wonder how much I'm unconsciously changing my picking attack? I know that I do things with my picking hand all the time without thinking about it at all, after many years of playing you just do it. It's reactionary just like a baseball infielder reacting to a ground ball, instincts take over. If they have to think about it, it's to late, base hit.
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> You're not gonna see caps above 10's- to maybe 100-pF which are insulated by air between the plates.
AM radio tuning caps were 365p+180p air dielectric, variable.
But they were also usually the biggest part in the radio, which rather confirms your point.
And they could be troublesome with vibration.
And at some sense there are no true air caps. Air is lousy at holding the plates in position. There's always a more solid (ceramic, phenolic) dielectric support bridging the plates. The area can be much smaller than the total plate area so it does not add huge loss, but can limit the voltage breakdown and add small loss.
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Yep, shoulda said "few-hundred pF" (which is what I really meant. The big tuning cap in a HP 200CD goes up to 617 pF/sect (more or less because you can bend the plates to fine-tune the capacitance), but it is way-huge compared to any typical coupling cap and really impractical for a guitar amp.
Those mica caps in my picture (the big brownish blocks) are big & heavy, and generally not practical to fit into a guitar amp unless you know you really, really want them and design the amp layout to accomodate them.
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Test results didn't sound to good for Mallory 150 whites, I've used a lot of those last couple of years. Thanks for sharing all the hard work Willabe! Platefire
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Test results didn't sound to good for Mallory 150 whites, I've used a lot of those last couple of years.
I'm not sure on that, it may be just that .02 value?
I have a lot of different values of the yellow and white Mallory 150's and they all are the same size except for the .02 value. It might just be that value or a bad apple?
I have not tried multiple samples of the same cap. :dontknow:
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It's reactionary just like a baseball infielder reacting to a ground ball, instincts take over. If they have to think about it, it's to late, base hit.
Unless maybe J Heyward is there backing up to field it & throw him out? :icon_biggrin:
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Guys, I know I will get booed for mentioning this. Here is a link to ceramic caps I prefer over silver mica. I have had problems with mica caps, especially if they are those glob looking types. The ones like Doug has and the Cornell Brown seem to be good, but I used these in my AC15 Build and have not used anything else for small value 50pf to 1000pf.
Maybe one of the more technical guys can look at the datasheet and give a clue as to why these may perform well:
https://product.tdk.com/info/en/catalog/datasheets/leadmlcc_conventional_fk_en.pdf
And maybe explain. I read all the time, get those ceramics out, but we all love those old amps that are just full of them. Maybe I just like harsh tones :laugh: , but I am being serious about these caps. They are tough and the leads are nice. It is odd the max voltage is 630 which seems low for a ceramic family.
Since we are speaking caps, I thought the ceramic could be included and if other have had good results with ceramic caps.
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Ed,
I find "cap talk" difficult without a visual of exactly what we're talking about. Sorry, but I need photos of what you are not a fan of/had issues with and what you (and others) find you like or are okay? A lot of ceramic caps do no mark their voltage ratings which is something I dislike. But I'm not prejudiced about ceramics especially 1n and smaller. But IMHO the best and most stable for these values is Styrene. Unfortunately they are expensive if using higher values with the right voltage rating and they can be sensitive to people with a heavy soldering hand as they melt. But if I had my druthers, I'd be using styrene at least for the smaller values.
Where do you locate those caps of which you speak of???
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Ed,
I find "cap talk" difficult without a visual of exactly what we're talking about. Sorry, but I need photos of what you are not a fan of/had issues with and what you (and others) find you like or are okay? A lot of ceramic caps do no mark their voltage ratings which is something I dislike. But I'm not prejudiced about ceramics especially 1n and smaller. But IMHO the best and most stable for these values is Styrene. Unfortunately they are expensive if using higher values with the right voltage rating and they can be sensitive to people with a heavy soldering hand as they melt. But if I had my druthers, I'd be using styrene at least for the smaller values.
Where do you locate those caps of which you speak of???
The link will give you the specs. They come from Mouser.
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"Ceramic" covers everything from 99 cent flower-pots to race-engine pistons. They are NOT all the same.
Your link includes C0G and X7R. C0G types are "perfect". X7R is mildly flawed.
> The link will give you the specs.
Only values and sizes. This link does not explain the different formulations.
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Guys - thanks so much for sharing these insights!
Chip
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OK, I ordered 3 Musicaps. I will replace .02 V1a coupling cap and then notice IF there is any change. Then I will also replace the post LTPI coupling caps & note the change. And then report back.
see reply 22 on thread
With respect, Tubenit
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"Ceramic" covers everything from 99 cent flower-pots to race-engine pistons. They are NOT all the same.
Your link includes C0G and X7R. C0G types are "perfect". X7R is mildly flawed.
> The link will give you the specs.
Only values and sizes. This link does not explain the different formulations.
I do not know the difference, but I first used the C0G doing the "Seeing Eye Mod" on a Boss pedal. Robert Keeley wrote an article on modding the pedal and specified these as "class 1 ceramic" in 2 locations and as with anything shipping costs encouraged me to purchase more. I did not know why he specified these and still do not. I do remember the article mentioned Class 2 ceramic to not be used for audio.
I have since reading your reply found COG/NPO are multi-layer and a link: http://www.cde.com/resources/catalogs/ceramperf.pdf (http://www.cde.com/resources/catalogs/ceramperf.pdf)
I am finding there is way more information on ceramic caps than I first thought and can easily understand why it is common for some ceramic types to cause unpleasant results. Therefore it is much easier just to stay away from them in audio.
They actually resemble a dipped cap as opposed to the circular type.
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I used quite a few Z5 ceramic disc caps in my AO-63 conversion project, mainly because the original was loaded with them. Some in the trem circuit, but others directly in the signal path. Should I have chosen a different cap?
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I used quite a few Z5 ceramic disc caps in my AO-63 conversion project, mainly because the original was loaded with them. Some in the trem circuit, but others directly in the signal path. Should I have chosen a different cap?
Only if you want to. Since they were already in there you really didn't choose them anyway. You never know tho, replacing them with the correct one may make it play in stereo. Hell maybe even 7.2 and display a 4K image.
I have a lot of amps with Z5 caps and I did not even know what the difference was until they started this thread. I think it is funny what you read on amp forums and how a LOT of people say ceramic? Bad? Then the same person covets their original old Valco.
That is what I meant when I mentioned Robert Keeley specifying the specific type. Who knows, maybe he knows something about modding the pedal I don't. I do find it interesting tho, because I never really considered all the different types.
I did not keep using them because I thought they delivered a better quality of sound, I simply like the size of the leads and the pretty blue color.
I also know you you are being genuine in your question being the sensitive guy you are.
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I'm very sensitive Ed. But my hearing suffers. Probably too much hair growing out of them! What's with than anyway?
I depend on you guys to steer me straight on this tone stuff so please drive carefully. :icon_biggrin:
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You never know tho, replacing them with the correct one may make it play in stereo. Hell maybe even 7.2 and display a 4K image.
I have a lot of amps with Z5 caps and I did not even know what the difference was until they started this thread. I think it is funny what you read on amp forums and how a LOT of people say ceramic? Bad? Then the same person covets their original old Valco.
That is what I meant when I mentioned Robert Keeley specifying the specific type. Who knows, maybe he knows something about modding the pedal I don't. I do find it interesting tho, because I never really considered all the different types.
I did not keep using them because I thought they delivered a better quality of sound, I simply like the size of the leads and the pretty blue color.
I also know you you are being genuine in your question being the sensitive guy you are.
:l2: Loved that Ed! And on Keeley? I don't think so. The pedal mods these guys do are practically highway robbery and the catchy name is just clever marketing preying on the innocents. BTW, if sent me his pedals I'd give him the Stink Eye mod. ;)
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I'm very sensitive Ed. But my hearing suffers. Probably too much hair growing out of them! What's with than anyway?
I figure the good lord feels we need extra protection in our openings as we grow older? Especially as our wives can get shall we say a little more emboldened with us as we age?
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Hey, I've got a doctor's certificate that I flash occasionally when I've said "huh?" too many times. She still thinks it selective hearing loss though! :icon_biggrin:
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Is that the same one that doubles for medicinal tone tubby-like product as well? :laugh: I usually get a little "loving" back of the head slap as my eyes are closed, back is turned, and totally defenseless...which feels just like a 400V B+ zap!
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I don't have the ear hair and neither does my Father who is still with us. I have also taken measures to protect my hearing since my fathers occupation caused hearing loss in him. He berated me every time he would see me jamming without earplugs when I was a kid. He would break the filters off 2 new cigarettes and stick them in my ears.
I am so glad he did cause I have a lot of musician friends that have hearing loss. I have some from a Military accident, but it only caused loss in the 16K area and it is very confined to the 16kHz area.
I believe Sluckey hears better than he admits tho as he did trash a matchless build for a Vox build and I know when he got the avatar cab he was grinnin like the Cheshire cat. We all lose some hearing due to age I believe. The reason I think so is the older you get usually the more you dislike new music. :icon_biggrin:
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I was grinning cause you said I would!
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Just two cents from a not-hugely-experienced amp builder: I've swapped-out and "ear tested" different style caps in different areas of my guitar amp builds... and every time, the orange drops have been my favorite. I could hear definite differences between each style of cap. I've also heard that they tend to be more stable under high temperatures which tube amp parts must endure.
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Which OD's?
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He would break the filters off 2 new cigarettes and stick them in my ears.
Now that's love, right there!
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So, to get the most out of your money with high dollar caps, they should go early in the preamp also I would think. IF, God forbid, I was spending $15 a cap, I'm only buying one. :laugh: And putting it in the first coupling cap position. Another place I'd consider would be in one of those fancy hi impedance input circuits I've seen.
Thoughts?
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break the filters off 2 new cigarettes and stick them in my ears.
If you light them 1st you clean out the ear hair and wax build-up :icon_biggrin:
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> found COG/NPO are multi-layer
NP0 (C0G) ceramic has been around a LOT longer than multi-layer construction.
Usta be they pressed a ceramic "plate", silvered both sides, dipped in slurry and fired. "One Layer".
I see they now have pFd/uFd values never dreamed of in the old days. I gather they roll ceramic like cookie dough, dice to small squares, stack with metalizing and fire, to get many times more pFd/uFd in smaller space.
> specified these as "class 1 ceramic" ...the article mentioned Class 2 ceramic to not be used for audio.
I had not heard that classification, and am not sure it is official, but there is a very clear distinction.
https://en.wikipedia.org/wiki/Ceramic_capacitor#Class_1_ceramic_capacitors
Class 1 is stable against temperature and voltage. It is also incidentally low-low-loss, "perfect".
Class 2 is much more uFd in the same space, but effective value varies wildly with voltage and temperature. The voltage variation means audio distortion. Sometimes this adds a nice edge, but unpredictably.
C0G has friends like N220 N1000 and even P100. These vary with temperature, but in a tightly defined way. In the old days we used coils and capacitors together to tune radios. Coil mechanical dimensions vary with temp, value changes, the radio drifts off-station as it warms. The ability to tune cap temp drift the other way allows much lower drift. The amount of drift that throws a radio from K-100 to Z-101 station is MUCH less than any drift we care about in audio. N220 etc caps are just as good as NP0/G0G caps for audio. However I sense that N220 etc have become specialty items (radios today are tuned other ways), and NP0 is old-school, expect C0G caps.
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Eventually I'll get my test-cap rig completed and do some listening myself.
So far the candidate caps are as follows:
- Mallory (CDE) M150 (metalized polyester)
- Fender Red (Kraft paper/Tin foil/Wax)
- CDE 418P (polyester film/foil; successor to OD 225P)
- Solen MKP-FC/PPM (metalized polypropylene)
- Auricap XO (metalized polypropylene)
- CDE 715P (polypropylene film/foil)
- Musicap (polypropylene film/foil)
- K42Y-2 (small green paper in oil)
- K40Y-9 (larger silver paper in oil)
- K75-12 (hybrid paper/PET (polyester) in oil)
- KSG-2 (Mica) or SSG-1 (mica)
- FT-2 (Teflon) or FT-3 (Teflon)
Where there's an "or" it's because some types don't offer certain values, and a substitution for the closest type with the specified dielectric/construction was made.
Everything after the Musicap is a Russian cap type. I'm mounting these thing inside a former GR decade resistor box, and the mica & teflon caps are rather huge & heavy. So I'll have to secure those to the box itselfas the switch alone can't support them. Even some of the oil types are quite heavy for their size... So that's slowing assembly down a bit.
Which type/brand have the smoothest sound, not too bright or too muddy or dry or metallic, just smooth, like velvet?
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... I first used the C0G ... Robert Keeley wrote an article on modding the pedal and specified these as "class 1 ceramic" ... I do remember the article mentioned Class 2 ceramic to not be used for audio.
I have since reading your reply found COG/NPO are multi-layer and a link: http://www.cde.com/resources/catalogs/ceramperf.pdf (http://www.cde.com/resources/catalogs/ceramperf.pdf)
I am finding there is way more information on ceramic caps than I first thought and can easily understand why it is common for some ceramic types to cause unpleasant results.
Skim the 6-part article until it mentions ceramic caps; you'll see the class 1 C0G measured near-perfect in testing (better than some film caps), while class 2 & class 3 ceramics exhibited a lot of distortion. All you really need to know from the data sheet you linked is that there are 3 classes, and C0G is class 1.
I used quite a few Z5 ceramic disc caps in my AO-63 conversion project, mainly because the original was loaded with them. ... Should I have chosen a different cap?
Should? Of course not; use whatever works for you.
I have a lot of amps with Z5 caps and I did not even know what the difference was until they started this thread. I think it is funny what you read on amp forums and how a LOT of people say ceramic? Bad? ...
Hopefully folks will note I've not said "bad" in relation to a cap in this thread. Though I did say one type of ceramic measured "horrible" because it had lots of distortion compared to other caps, where low distortion was the test criteria. Additionally, I brought up the distortion piece as a way to help explain why some caps sound differently than others, as it is an objective measurable quantity (though you can subjectively screw up the measurements by not having a low-enough-distortion test signal and/or buffering).
Eventually I'll get my test-cap rig completed ...
Which type/brand have the smoothest sound, not too bright or too muddy or dry or metallic, just smooth, like velvet?
My cap substitution box is not built yet.
Further, I can tell what my impressions are testing the caps in a specific amp circuit, using a specific guitar and speakers; however, that may not translate to how they will/won't sound when you use them. I will not be telling anyone what cap to use. Others can/should try for themselves if they are inclined. Why? Because I've tried expensive caps in amps before and generally found the change not worth the cost. However, I am curious about the specific types I bought for this test.
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When you say distortion , what are you talking about exactly? Not like a pedal distortion, is that correct?
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When you say distortion , what are you talking about exactly?
Post #1 of this thread (http://el34world.com/Forum/index.php?topic=19534.msg202775#msg202775); the linked multi-part article...
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I've found that article in PDF format here are the links for all of it :icon_biggrin:
http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_1.pdf (http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_1.pdf)
http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_2.pdf (http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_2.pdf)
http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_3.pdf (http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_3.pdf)
http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_4.pdf (http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_4.pdf)
http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_5.pdf (http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_5.pdf)
http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_6.pdf (http://www.waynekirkwood.com/images/pdf/Cyril_Bateman/Bateman_Notes_Cap_Sound_6.pdf)
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... I first used the C0G ... Robert Keeley wrote an article on modding the pedal and specified these as "class 1 ceramic" ... I do remember the article mentioned Class 2 ceramic to not be used for audio.
I have since reading your reply found COG/NPO are multi-layer and a link: http://www.cde.com/resources/catalogs/ceramperf.pdf (http://www.cde.com/resources/catalogs/ceramperf.pdf)
I am finding there is way more information on ceramic caps than I first thought and can easily understand why it is common for some ceramic types to cause unpleasant results.
Skim the 6-part article until it mentions ceramic caps; you'll see the class 1 C0G measured near-perfect in testing (better than some film caps), while class 2 & class 3 ceramics exhibited a lot of distortion. All you really need to know from the data sheet you linked is that there are 3 classes, and C0G is class 1.
I used quite a few Z5 ceramic disc caps in my AO-63 conversion project, mainly because the original was loaded with them. ... Should I have chosen a different cap?
Should? Of course not; use whatever works for you.
I have a lot of amps with Z5 caps and I did not even know what the difference was until they started this thread. I think it is funny what you read on amp forums and how a LOT of people say ceramic? Bad? ...
Hopefully folks will note I've not said "bad" in relation to a cap in this thread. Though I did say one type of ceramic measured "horrible" because it had lots of distortion compared to other caps, where low distortion was the test criteria. Additionally, I brought up the distortion piece as a way to help explain why some caps sound differently than others, as it is an objective measurable quantity (though you can subjectively screw up the measurements by not having a low-enough-distortion test signal and/or buffering).
Eventually I'll get my test-cap rig completed ...
Which type/brand have the smoothest sound, not too bright or too muddy or dry or metallic, just smooth, like velvet?
My cap substitution box is not built yet.
Further, I can tell what my impressions are testing the caps in a specific amp circuit, using a specific guitar and speakers; however, that may not translate to how they will/won't sound when you use them. I will not be telling anyone what cap to use. Others can/should try for themselves if they are inclined. Why? Because I've tried expensive caps in amps before and generally found the change not worth the cost. However, I am curious about the specific types I bought for this test.
HBP, I was not referring to your posted comments. It is simply common that I read to replace ceramic especially in tone stacks with silver mica. I simply had a supply of silver mica caps that were bad. They came from Weber and I had a couple of people not happy with their amps.
Long story short, it took me a long time to find it on the first comeback. I replaced them with the black ones like Doug sells and the problem disappeared but my apprehension to using them has not.
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He would break the filters off 2 new cigarettes and stick them in my ears.
Now that's love, right there!
I knew someone was going to pick that out. It is true, but remember I am talking about when Cigarettes were 30 cents a pack so not as much love as it would be today. :laugh:
They actually worked well.
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when Cigarettes were 30 cents a pack
I think you could make the case that 30cents back then was worth more than $8 today :icon_biggrin:
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Just an FYI on MusiCaps caps. I wanted to make sure which end should point where? So I did the outer foil test that I normally do.
top picture on Reply #13 on this ARCHIVE thread: http://el34world.com/Forum/index.php?topic=11427.0 (http://el34world.com/Forum/index.php?topic=11427.0)
There was a HUGE difference in noise/quietness having the "correct" end towards ground. MUCH much more pronounced then doing the same experiment with Orange Drop PS caps of the same value. Dramatic difference.
Same value OD PS cap does have a quiet end. But the noise difference on the OD PS caps was no where near the amount of dramatic difference of the Musicaps. I only bought 3 caps in .02 and .047 values & the dramatic difference between quiet and noise was evident on all 3 caps. You can't miss the difference on the Musicap.
The caps came with a red lead and a white lead. The white lead goes in the direction that a normally marked end that an Orange Drop would go. So for an example where a marked end of an OD cap goes towards the tube socket, the white lead end of the Musicap goes towards the tube socket. (see photo reply #13 on ARCHIVE thread of foil orientation)
In contrast, sometimes on some values of the OD caps I have to listen very carefully to hear the noise difference.
I don't know IF that means anything special about Musicaps being "better" or more transparent or not? Maybe they are not. What I can say conclusively is that the values I tried on the Musicaps gave a very easily discerned transparent difference between the ends.
It also seemed like the quiet end of the Musicap is quieter then the quiet end of an OD of the same value. AND that the noisy end of the Musicap is noisier then the OD of the same value. That was my impression.
Probably won't have a chance to install these and A/B them til the weekend but I will report the results later. These are going into the D'Mars which has ALOT of caps in the signal path. So remember, I am only changing out 3 to see IF only 3 would make any difference? Given the high cost of these caps, I wanted to see if only a few would make a noticeable difference.
with respect, Tubenit
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Hey all, thanks for posting all of this information. At some point I'd like to build a simple amp that I could use to test different components to hear for myself what they sound like. Everyone talks about how different types of capacitors sound different compared to one another, but I don't have enough experience building amps to know just how different they sound.
If I were going to build a 5F1 in order to test different caps, would I put a rotary switch connected to a bunch of different caps in place of C2 or C3 (using Doug's schematic)?
If I used a solderless breadboard rather than one of Doug's boards, would that be an easy way to test different tone stacks?
Assuming I had enough money to spend on transformers, could I easily test different power/preamp tubes with a circuit? I'm curious about how a KT88- or 6550-equipped Champ would sound.
Sorry about all the questions, I'm just trying to pick up as much as I can from everyone here. I still have a LOT to learn from you guys!
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look at willabe's thread on his breadboard for info on rotary switch, and 5f1 layout.
http://el34world.com/Forum/index.php?topic=18354.msg200504#msg200504 (http://el34world.com/Forum/index.php?topic=18354.msg200504#msg200504)
I built this amp last year, tried kt88, 6550, and EL34 in the PA section, currently using the KT. you can mate the PA section with any pre-amp
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Thank you Shooter, for positing the link in answer to Plaidzebra's question. :icon_biggrin:
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There was a HUGE difference in noise/quietness having the "correct" end towards ground. MUCH much more pronounced then doing the same experiment with Orange Drop PS caps of the same value. Dramatic difference.
Same value OD PS cap does have a quiet end. But the noise difference on the OD PS caps was no where near the amount of dramatic difference of the Musicaps. ,,,,,, the dramatic difference between quiet and noise was evident on all 3 caps. You can't miss the difference on the Musicap.
What I can say conclusively is that the values I tried on the Musicaps gave a very easily discerned transparent difference between the ends.
Now wait a dog gone minute now, :BangHead: :cussing: :laugh: Som'thin screwy is going on here. :think1:
When this 1st started, on testing for the outside foil, I found, to my ear any way, that the SMALLER the caps value, the HARDER it was for me to hear a noise difference. BUT, you and Gezzer found the opposite, the LARGER the value of the cap, the HARDER it was to hear a difference. :think1:
So, at this point, my conclusion is : There MUST be something different in the way you (and Gezzer) are testing caps for the outside foil lead than I am? Because, ..... I'm getting the opposite results. :dontknow: :think1:
And, out of the caps I've been able to test for outside foil, in my test rig, I found that the Musicap was the LOWEST in difference between outside foil and inside foil lead. PLUS the Musicap were WAY lower in noise, from outside/inside, of any of the other caps I tried/tested. :dontknow: :think1:
Of all the caps I have tested;
1st; I measured them for capacitance value, no big deal, just to see if their close.
2nd; I tested and marked them for 'outside foil'. (My test's, only 2 caps, showed what you got on the Musicaps, white lead is the outside foil lead.)
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Wow! Yeah, I'd say our experience is quite different. I did the test with Orange Drop and Musicaps last night side by side.
I find above .1 to be very difficult to assess and below .002 also somewhat difficult. The range between .0047 to .068 is easy to hear the difference with smaller values easiest to hear. I always use the clean channel of my amps to test the caps.
The amp is quieter with .1 & is noisier with above .002 in my experience. In other words, with .1 the difference in quietness either direction isn't as great in comparison to a .02 AND the difference in noise with the .002 isn't as great with either direction.
I have always tested like in this photo. See how my thumb and forefinger is sort of "pinching" the cap. After I have the wires hooked up, I pinch and open and pinch and open and pinch and open .......... etc ......... my thumb and forefinger.
Then I switch the cap around and do the same thing. It is the pinching and opening that reveals which side is quieter to me. When the quiet end is towards ground & I pinch the cap ............ it does not make nearly as much noise as when the noisy end is towards ground and I pinch the cap. The noise increases when I pinch the cap and is quieter when I am not pinching the cap.
Anyhow, that's what I do and it seems to work well for me as my amps are very quiet at idle. Like on my D'Mars, I can set the amp up like this:
If you walked into the room with the amp on with the clean channel ........... I am not sure one would know the amp is on audibly. However, without changing any settings on the amp ........... IF I banged a chord out, I think it would startle someone because it is so loud because of how loud I had the settings dialed in.
With respect, Tubenit
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Brad, if you have time to try it ...........
Take a Musicap and Orange Drop of the same values.
Listen to the difference in noise between pinching and opening your thumb & forefinger with the caps either direction
VS.
the difference in noise with the caps either direction without pinching & opening your thumb and forefinger.
The pinching and opening motion reveals to me what end is the quietest not just clipping them in either direction. I think you will find the pinching and opening motion will prove a greater contrast in noise with the Musicap? Maybe?
Again, my amps are quiet at idle. My D'Mars at idle would be MUCH quieter then the Fender Princeton Reverb (I used to own) at idle even if the D'Mars volume was set at twice the PR volume.
With respect, Tubenit
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See how my thumb and forefinger is sort of "pinching" the cap. After I have the wires hooked up, I pinch and open and pinch and open and pinch and open .......... etc ......... my thumb and forefinger.
Then I switch the cap around and do the same thing. It is the pinching and opening that reveals which side is quieter to me. When the quiet end is towards ground & I pinch the cap ............ it does not make nearly as much noise as when the noisy end is towards ground and I pinch the cap. The noise increases when I pinch the cap and is quieter when I am not pinching the cap.
Listen to the difference in noise between pinching and opening your thumb & forefinger with the caps either direction
VS.
the difference in noise with the caps either direction without pinching & opening your thumb and forefinger.
The pinching and opening motion reveals to me what end is the quietest not just clipping them in either direction. I think you will find the pinching and opening motion will prove a greater contrast in noise with the Musicap?
I'm doing the exact same thing as you are. :dontknow: I wonder if it's my test rig box I built? :think1:
I had a friend over a few weeks ago and I showed him my cap test rig box because I wanted to see if he would hear the same thing that I was. That the smaller the cap, the harder it was to hear a difference. He heard what I'm hearing.
He's in his late 50's, is a guitar player, is a PHD in science/chemistry and his father 1st got him going in electronics when he under 10, as he was a Ham radio guy. He has used all kinds of test equipment over the years doing research for developing/refining/problem solving for major chemical companies products manufacturing. He has been teaching me how to use my scope.
I'll play around with some caps again.
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Here's what I posted earlier in my bread board thread;
1. Mallory 150/white/630v/22.02nF.
2. Mallory 150/yellow/630v/22.02nF.
3. Jupiter/yellow/600v/20.39nF.
4. Jupiter/red/600v/19.28nF.
5. SoZo/blue/400v/22.02nF.
6. Musicap/600v/23.00nF.
7. AuriCap XO/600v/20.78
8. Mojo Mustard/630v/22.05nF.
9. Orange Drop/400v/22.74nF.
10. OD 715/400v/22.30nF
Here's what I think so far after 3 different rounds of playing on 3 different days, playing single notes and full chords, both with -FB and without -FB;
Also, and I don't know what it means, was when I tested for the caps outside foil lead, some were way noisier than others. (I mean how noisy the cap is with the outside foil lead hooked up to the test amps input.) The Mallory's were the nosiest with the white being the worst. The Musicap and AuriCap were by far the quietest. The quite 1's had very little difference in noise when flipping the switch to flip the caps leads. And on the outside foil cap lead to the test amps input they were way quieter than the other caps on their outside foil lead. Big difference.
I was thinking, before these tests, that the fatter the cap the more shielding it would have from outside foil lead to the inside foil lead. So larger values/larger voltage rating(fatter cap) would have more difference when switching leads. A 0.1uF cap is way easier to hear a difference than a .0047uF cap, I have a very hard time hearing any difference in leads on a Mallory white 150. (I know that Tubenit and Gezzer have posted they hear the opposite. (http://el34world.com/Forum/Smileys/default/dontknow.gif) ) But the Musicap was the quietest and is the thinnest.
My friend and I came to a possible conclusion that the smaller/shorter caps were picking up our fat little thumb and finger being closer to the caps leads than the bigger/longer caps. :dontknow:
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Brad,
Did not know you had a scope. I quit using the finger/thumb method because I have had a few cases where I am uncertain and could not determine to my satisfaction the correct orientation. Here youtube video showing you how to use a scope to determine.
https://www.youtube.com/watch?v=BnR_DLd1PDI (https://www.youtube.com/watch?v=BnR_DLd1PDI)
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Great video Ed.
I test my caps using a distortion or Fuzz pedal to help with ramping up the noise level to be heard easier. I initially tested a number of caps a while back with and without holding/pinching the caps and noticed differences between the two methods. I would get the opposite readings "most" of the time but not always (between holding the cap or not). I ended up using the holding method primarily from that point onward to positive results. There's no need to go to the extremes of the guy in the video to build a simple tester. In fact you don't need anything but a guitar chord but this is too slow and rather cumbersome. Here's a simple small cap testing switch box below with alligator leads for the cap under test and an input jack for making it faster & easier to plug the amp chord into. It works well and is fast with the switching ability to go back and forth quickly on the fly between the two positions which is easier to hear those smaller noise differences. The little crude drawing is as if viewed from the backside and "Normal" means the colors are correct, "Reverse" means they are opposite to mark the cap under test properly.
One other note of interest from this is that the guy is correct in noting & explaining the lead immediately exiting the cap. It is considered the high impedance end of the cap and also becomes part of the grid wiring from that point onward. This means that your signal is very sensitive at this point to induced hum & interferences just as your input leads are from your input jack. Keep these wires as short as practical and away from B+, high current wiring, other signal wires, etc... if this wire actually is to go near anything as described or for a run of any distance then connecting to and using shielded cable would be appropriate. An ounce of prevention...
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OK, I did an experiment comparing Musicaps to Orange Drop PS caps in just a few areas. To be honest, I did not expect to hear much of a difference in tone given the number of caps in the signal path in this amp.
I changed the .02 on V1-1 from the Orange Drop PS to the Musicap .02 There was somewhat between a noticeable difference to slight significant difference. It was NOT a dramatic difference to my ears. The caps were different and I would not say that one was truly "better" then the other.
I think with it being the first cap in the signal path that this may explain why I could hear a difference between the two. I am confident that most of the forum members could be blind folded and pick out which cap was which. It was that significant of a difference, IMO.
The Orange Drop PS had a more chimey (maybe bell like) tone. It had a little grit and sort of sounded like it was more midscooped (which doesn't make sense) when playing chords meaning I could hear the bass and treble notes best and the mids were somewhat less transparent. It was reasonably smooth but when a note or chord was strummed, there seemed to be an "attack/spike" initially with the notes began fading out and losing strength.
In contrast, the Musicap was much smoother. Bass, mids and treble were all transparent and articulate. Mids were very warm and very transparent compared to the Orange Drop. The Musicap had significantly more sustain then the Orange Drop and the notes did not have the initial spikey attack and the notes held their tone/body well. The main thing I liked about the Musicap was how transparent it was, how smooth it was and the length of the sustain. The sustain was biggest surprise.
What I don't like about the Musicaps is soldering them in. It's reasonably easy but the Orange Drop with stiff wire leads is much easy to solder into turrets then the stranded wire. They are also expensive at $10+ each. And the length is greater then the Orange Drops which I don't like.
When I did this test, I simply A/B'd them back and forth about a dozen times over 30 minutes playing single note leads, chording and finger picking. I was able to change from one cap to the other within seconds.
The Musicap gave what I consider a reasonable improvement in the smoothness, transparency (especially in mids) & a surprising increase in sustain. I left the cap in.
The one Musicap on the clean channel did NOT make any discernible difference to the overdrive channel that I could tell.
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And did you change the PI caps?
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The next thing I tried was replacing the pair of Orange Drop PS .05 caps with Musicap .047 caps in the coupling caps post LTPI.
I could hear a difference between those two, but it was just different and not necessarily "better". I liked the OD caps about as well as the Musicap. The Musicap was slightly more transparent. I don't think there was any improvement in smoothness or sustain in this position that I could hear. Perhaps that might be because those caps were further down the signal chain.
I was not able to effectively A/B these within seconds like on the first coupling cap. So, it was more challenging to define the differences. I have left the Musicaps in the post LTPI coupling cap positions for now. Not confident that I could clearly discern which was which if blindfolded?
I could not tell a difference in chime or attack with Orange Drops vs. smoothness in Musicaps. They seemed very similar in tone in those regards.
With these caps in place, I think the overdrive seemed a little more transparent but not a big difference.
I think I'd like to replace the one .01 coupling cap after the first gain stage of the overdrive and see what changes if any there are?
Some thoughts I have after experimenting with this. 1) I think the first coupling cap is worth changing to a Musicap. 2) There may be diminishing benefits changing other ones, but I don't know? 3) This is kind of hard to describe and explain but if I had all Musicaps in the amp and they continued to make the amp more and more transparent, ............. I am not sure I'd like an amp with that degree of transparency? I think it might sound good for a jazz amp or for an amp for an acoustic guitar not sure about a solid body electric?
IF I get around to changing out something on the OD channel, I will report back again.
With respect, Tubenit
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One thing I am wondering about with the Musicaps is that given their leads are stranded wire that is flexible, I don't know if that is a hinderence in a combo amp ............ OR if that might actually be like having a shock absorber (flexible wire) and allow the caps to not add any microphonics? I have no idea if it's a plus or a minus?
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Thanks for posting your test results Tubenit. :icon_biggrin:
I look forward to hear about what you hear if you change the one .01 coupling cap after the first gain stage of the overdrive.
The Musicap at this point, I'm leaning towards as my favorite cap out of the caps I've tried.
It is smooth sounding to me but it has some 'hair' (not too much) and warmth to it that I like. It seems very well balanced from low end to high end. :icon_biggrin:
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Tubenit, may I ask you to perform a different cap test please?
Since most here like using the Mallory150 or the ODs as they are most common and Doug also sells these - would it be too much trouble to try subbing in the Mallory150? You are very good about describing your results and to me, I've often wondered about these two compared with each other.
Your description of the OD is exactly what I seem to notice & experience as well with the Mallory seemingly being a bit more similar to the Musicap side of things (going by your description)? So maybe the Mallory's are just fine without the expense & wiring issue associated with the Musicap?
Thanks for your efforts!
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look at willabe's thread on his breadboard for info on rotary switch, and 5f1 layout.
http://el34world.com/Forum/index.php?topic=18354.msg200504#msg200504 (http://el34world.com/Forum/index.php?topic=18354.msg200504#msg200504)
I built this amp last year, tried kt88, 6550, and EL34 in the PA section, currently using the KT. you can mate the PA section with any pre-amp
I like the schematic, how does the amp sound?
(If nobody minds me asking.)
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I'd like to hear that from Tubenit also. :icon_biggrin:
For me, the white Mallory sounded nothing like the Musicap, nor did the yellow Mallory. The OD 225 (PS?) sounded closer to the Musicap than the white Mallory but still noticeably different.
BUT........ I've only tested 1 of each cap, so..........
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I like the schematic, how does the amp sound?
Which schematic?
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Great video Ed.
I test my caps using a distortion or Fuzz pedal to help with ramping up the noise level to be heard easier. I initially tested a number of caps a while back with and without holding/pinching the caps and noticed differences between the two methods. I would get the opposite readings "most" of the time but not always (between holding the cap or not). I ended up using the holding method primarily from that point onward to positive results. There's no need to go to the extremes of the guy in the video to build a simple tester. In fact you don't need anything but a guitar chord but this is too slow and rather cumbersome. Here's a simple small cap testing switch box below with alligator leads for the cap under test and an input jack for making it faster & easier to plug the amp chord into. It works well and is fast with the switching ability to go back and forth quickly on the fly between the two positions which is easier to hear those smaller noise differences. The little crude drawing is as if viewed from the backside and "Normal" means the colors are correct, "Reverse" means they are opposite to mark the cap under test properly.
One other note of interest from this is that the guy is correct in noting & explaining the lead immediately exiting the cap. It is considered the high impedance end of the cap and also becomes part of the grid wiring from that point onward. This means that your signal is very sensitive at this point to induced hum & interferences just as your input leads are from your input jack. Keep these wires as short as practical and away from B+, high current wiring, other signal wires, etc... if this wire actually is to go near anything as described or for a run of any distance then connecting to and using shielded cable would be appropriate. An ounce of prevention...
Yes, he goes a bit overboard. I built one and also used a switch and have used a patch cord with a fuzz and a champ. None of this is as easy to me as what he first does in the video using a BNC with clips. I simply do it this way now because I trust the scope and you only have to place it once and no need to switch back and fourth.
What I found interesting is the caps he showed that were marked, both were opposite of what I thought. Since I have checked and all old sprague caps mark the opposite, whereas sozo and the yellow astrons in Brown and Tweed amps all mark the the outer shield.
So there is no standard. Also I have a 5C1 champ that have OD 715 and I reversed all of them with no measurable increase in noise.
I can hear a difference between caps, but I end up using 2 or 3 different types in my builds since I only keep good quality caps. I use what fits the best and sometimes what looks best. If I am using a red board, I prefer black caps and will recycle a Black Beauty in a minute. I also use Aerovox white caps that have a similar shape of Musicap against a red board too.
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I have compared Mallory 150's to Orange Drop 715's and also Orange Drop PS series in numerous amps.
Overall, I am not a fan of Mallory caps thru out an entire amp but I do like them quite well in LTPI & post LTPI coupling caps and I think they sound decent in an overdrive channel. I think they give a somewhat compressed and warm tone.
I do not care for them in a preamp or in tone stacks and have found that they lack transparency compared to other caps that I have tried. I have not found them to have good harmonics in the preamps of my specific amps.
One amp I built where I used all Mallory 150's sounded like I had a thin blanket over the speaker. I changed that particular amp to all Orange Drops in the PreAmp and tone stack and thought it sounded fantastic after that. I lost some of the harmonics in the higher frequencies with the Mallory's.
Regarding trying that again in my D'Mars preamp, I am not going to remove the soldered Musicap to test the Mallory's. I've compared them enough in previous builds to be comfortable with my findings.
With respect, Tubenit
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I changed that particular amp to all Orange Drops in the PreAmp and tone stack and thought it sounded fantastic after that.
To be clear, you changed to OD PS series caps?
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Brad,
I remember in at least two of the amps that I started with Mallory's but change them I changed to the Orange Drops 715's that Doug carries not the PS series.
Another way of stating what I am trying to say is with the Mallory's in the preamp & tone stack, I did not find the note/string definition in chording to articulate very well. It was OK with power chords or single note lead guitar but lacked transparency in strumming or fingerpicking chords in a way that is trying to accent and articulate specific notes within that chord. Hope that makes sense?
It did seem like the Mallory's eliminates some of the high end frequency "hash" but it eliminated transparency in the preamp tone along with that. I could see all Mallory 150's thru out an amp like an 18watt using EL84's working quite well. IF the same amp was running 6V6's (that are not as chimey, IMO), then I'd want Orange Drops in the preamp.
One of the best overdrive tones I've ever had was with the original Tweed Overdrive Special and it had a mix of Orange Drops in the Preamp and Xicon and Mallory 150's after the preamp. I did the same thing in my original Carolina Overdrive Special also.
http://www.soundclick.com/player/single_player.cfm?songid=9488477&q=hi&newref=1 (http://www.soundclick.com/player/single_player.cfm?songid=9488477&q=hi&newref=1)
With respect, Tubenit
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Ok, just wanted to be sure which type of OD's you were talking about. :icon_biggrin:
But are the 715's still your favored OD cap over the OD PS (225?) series? (Some how I got the impression you favored the OD PS series, at least latter on? :think1: )
Nice playing BTW. :icon_biggrin:
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Yes, I prefer the Orange Drop PS in the Tweed BluezMeister and the D'Mars ODS which are D-style inspired amps.
In the Carolina Blues Special, TOS, HoSo56 and others, ......... when I used Orange Drops I used 715's. In the CBS, I definitely preferred the 715's and would choose them over the PS series.
There are so many factors involved around tone and caps in my opinion. Speaker, guitar, player, topology of the amp schematic, pedals or not, tube reverb or vibrato or not, type of music you like. I think it's kind of an amp by amp thing.
I have not cared for amps with all Mallory 150's because they lack some transparency. Conversely, I am guessing I would not like an amp with all Musicaps with a solid body electric because it would sound too transparent and perhaps hi-fi-ish? I think a preamp with all Musicaps and an LTPI and after having Mallory's could sound really great.
With respect, Tubenit
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Ok, thanks, I just want to be sure I'm understanding you. :icon_biggrin:
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I like the schematic, how does the amp sound?
Which schematic?
Sorry, thought it was included with the post. Not sure if it will come up right.
LeGourmet.jpg (http://166.63.127.229/Forum/index.php?action=dlattach;topic=19534.0;attach=55230)
Don't really see many SE amps with a couple of cold clippers. Assuming they are cold, but now looking at the plate resistors I am not sure.
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I built my cap substitution box. I used a General Radio Decade Resistor which had a burned-open resistor section as a donor for the chassis box. It has 3 switches which have a position for each of the caps I noted in my earlier post (http://el34world.com/Forum/index.php?topic=19534.msg202811#msg202811), with a switch for 0.022uF, 0.047uF and 0.1uF. There is a 4th switch of select which of the value-switches is active.
Note if you copy my path: The black terminal on these GR products can be connected to the case via a metal clip on the terminal with no plastic bushing. If you have that clip connected, you have a 50/50 shot of placing the case at plate voltage of the coupling cap you're replacing. So please, check carefully with a meter from terminal to guitar strings to know if you're setting yourself up for a big shock.
The pictures below show the assembly of the caps on the various switches. The bigger caps (some oil caps, but all mica and Teflon) had to mounted on the case itself and wired to the switch.
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WOW! Very nice work! :icon_biggrin:
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I tried using my substitution box to replace the coupling cap on V1 of an Epi Valve Jr. See picture below for where the cap box was connected in circuit.
I broke apart C1 with some cutters to leave leads extending above the p.c. board, to which I attached my cap sub box with alligator jumper clips.
Bottom line, I heard essentially no change among any of the cap positions. I used a 2x12 cabinet loaded with Scumback speakers (http://el34world.com/Forum/index.php?topic=17076.msg172306#msg172306) to do the listening test, as they're much clearer han the onboard Valve Jr speaker. I tried all pickup combinations of both a Les Paul & a Tele (both with very good pickups).
Further, the Mallory M150 and the Russki Teflon caps are in adjacent switch positions, representing the theoretically "best" & "worst" caps of the test batch, which provided very fast switching between the two. Still, I couldn't hear any difference between the two settings that couldn't be put down to playing difference (picking, volume, etc).
IF here's an actual sonic difference between the caps tested, then this amp isn't allowing them to be heard. This amp is completely stock except for the cap I broke apart to provide a test point. I did, however, expect there to be a audible difference in the V1 coupling cap position.
The only caveat is my testing was done playing cleanly, and at relatively low volume (I'm an apartment dweller). However, if the differences are so subtle they can't be heard when playing clean, then the cost of the tweak-caps isn't justified in my opinion. An alternative explanation is the existing output transformer, caps or some other circuit element doesn't allow the change to be heard. I don't know if/when I might make upgrades to this amp's transformers, etc.
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Do you still have a Fender type Champ or Princeton?
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I've got a pretty decent 5E3 copy. I may try the sub box in that amp for a 2nd opinion.
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Testing high end caps for subtle sound differences in an Epi VJ may be kinda like taste testing fine wines thru a straw. I can't say for sure. All my wine comes in a box from RiteAid! :icon_biggrin:
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Believe it or not, with good speakers that amp doesn't sound bad as-is. I'm pretty sure mine is Rev 3, with most of the online suggested mods already in-place stock. It's also reasonably close to a Champ circuit.
That said, I don't trust that the OT isn't holding the amp back.
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Yes, try another amp.
I found that I need to be able to focus and not be distracted.
Some days I hear more of a difference than others. :dontknow:
I also had to get the volume up to ~11:00 on the Champ to hear the difference clearly. (Fender Strat with stock run of the mill output PUP's.) Volume set at ~2:00 and past seemed to lessen the difference in change. :dontknow:
And I have to set the K bypass rotary switch to the 4.7uf or the 10uF bypass cap. :dontknow:
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I've got a pretty decent 5E3 copy. I may try the sub box in that amp for a 2nd opinion.
I think that is a good idea! And that's a nice amp! I remember you jamming thru that one. Good tone to it. So, I think it would be a reasonable testing ground.
With respect, Tubenit
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I tried again with the 5E3, replacing the 1st coupling cap on the Bright (tone control) channel.
Still no appreciable difference for any of the cap types. The volume was down around 2. I will confess I'm also getting a cold. However I heard very distinct differences switching from 0.1uF to 0.047uF and 0.022uF. I like the smaller coupling cap values in that amp better. Speaker is a Weber 12A125.
Maybe more volume and/or more harmonic content from distortion is needed. I'll try to arrange a time/place to crank that amp up more. I only tested with the Les Paul this time but used all pickup settings. This amp has all paper-in-oil coupling caps except a single orange drop running into the phase inverter grid.
I'll post an update once I get a chance to test under different circumstances.
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I tried again with the 5E3, replacing the 1st coupling cap on the Bright (tone control) channel.
That's the same tone control I hooked up on the bread board for the Champ. I had to set it ~1:00 to 2:00 to hear the most difference in the caps with the volume at ~11:00 to 2:00, with a 1st stage bypass cap of 4.7uF or 10uF. Volume and tone control on the guitar (Strat) FULL UP, used neck (mostly) or middle PUP. :dontknow:
The volume was down around 2. I will confess I'm also getting a cold.
Maybe more volume and/or more harmonic content from distortion is needed. I'll try to arrange a time/place to crank that amp up more.
I think you will hear it. I set this up on my BB to see if I could hear any change in caps for myself. I think I do hear a change but it's no where near as drastic as a speaker change can be. At this point whether the change is enough to justify the price I can't say yet. For me more testing needs to be tried.
I think there's possibly a lot of variables involved with this that are way different than swapping out speakers.
For example you have said that after you built your Standel you could hear that a Fender set clean wasn't as clean as you/we thought, had some 'hair' to it.
So if we set the test amp clean then any harmonic distortion added by a different cap might not be noticed as the cap, because what we're hearing is the same as a volume change on the amp? Say like going from ~2 or 3 to ~4 or 5 on a BF?
My thought at this point is, IF the caps are making a difference in tone, and I believe they are, they need some distortion (harmonic) coming in for them to multiply. If the caps 'flaws' are creating harmonic distortion then if they get some extra harmonics coming in they have a little something more to do their thing with? :dontknow:
I say this because, why am I hearing the most difference at a certain volume and tone control setting? I don't think it's db's as it's only a 5w amp. I think it's having enough signal developed in the signal chain to drive the cap enough? :dontknow:
Is there a non-linearity effect happening by driving the cap's a little harder? So now we hear the caps 'flaws'/'artifacts'? :dontknow:
I do think that as guys play with this, we will start to get some answers of what is going on. :icon_biggrin:
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If you look back at the article's distortion measurements, many of the added harmonics fall in the range of -60 to -120dB, which is a range of 1/1,000th down to 1/1,000,000th of the fundamental frequency (yep, 1-millionth or 1ppm).
I'm thinking a broadband noise, like pink or white noise, might be a good way to hear how a cap influences a broad range of frequencies. Perhaps this broadband test is why hearing the cap with a distorted signal helps highlight differences.
I'll try again later with a distorted sound and see what impressions I have.
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> broadband noise
Maybe.
I'd think a super clean Sine would expose more stray hash.
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You know/understand way more than I do. I trust your thinking/experience on amps/electronics, I'm just shooting in the dark and throwing out ideas I have that maybe will help? :dontknow:
But IIRC all his test's on caps were only 18dcv at the most. We're in a higher acv/dcv setting.
I'm still wondering about a non-linearity effect happening?
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I think PRR is correct -( as always, in my book :icon_biggrin:) looking at complex signals with a scope just hurts my brain!
I do have a question though, when you play a chord - pick one - would each string strummed be considered a fundamental freq?
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As a result of reading 70% of the above posts I ordered a Musicap to inspire my 2 cents.
I have a single ended Deluxe Reverb'ish circuit that I did a simple test with tonight. I ran it through an Eminence EM12 so as to keep speaker distortion out of the equation.
It had a single .1uf Mallory 150 white as the last coupling cap before the single 6V6 and I made a little quick switch rig so that I could blind A/B it with a .1 Musicap while I had a friend change the switch position as I played.
We were both able to hear reduced distortion when he switched in the Musicap. It was definitely cleaner and gave the impression of being "fuller". We noticed it more with the amp dimed, and the Musicap seemed to take away some distortion sizzle/hash that I would have previously attributed to inherent tube distortion. It gave me the impression that the tone was more open and less compressed/distorted.
We also cranked up the reverb and felt like there was more "open space" for the reverb to fill when going through the Musicap.
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Well, well, bout time you showed up to visit us brother. :icon_biggrin:
Very glad to hear from you Dave! hehehehe.... :happy2: (Check my last PM to you please.)
Thanks for helping test caps for tone and posting what your hearing.
I want to say that in the test rig I have set up, Fender Champ 5F1, for me, that so far, I'm leaning towards the Musicap, ~BUT~, I do like a bunch of the other caps set up in the same test rig.
I also think you would hear a difference trying the Jupiter yellow, OD PS/225 (polyester), OD 714(polyprop) Fender Red, or any of them. Which you would like best would be up to you.
Some are more drastic in difference and I think it's really up to the individual and what amp/circuit/guitar/style of playing, to choose which they like the best?
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We were both able to hear reduced distortion when he switched in the Musicap. It was definitely cleaner and gave the impression of being "fuller". We noticed it more with the amp dimed, and the Musicap seemed to take away some distortion sizzle/hash that I would have previously attributed to inherent tube distortion. It gave me the impression that the tone was more open and less compressed/distorted.
Now that is a better description, and makes more of a case for spending the $ than any cap maker's marketing I've read. Nice to "see" ya again buddy!
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I think PRR is correct -( as always, in my book :icon_biggrin: ) looking at complex signals with a scope just hurts my brain!
Yes, the single pure sine and a spectrum analyzer is the way to go when using measuring equipment. What I suggested is more about "can I hear a difference" without quantifying "why I hear a difference."
... when you play a chord - pick one - would each string strummed be considered a fundamental freq?
By definition, yes. Multiple fundamental frequencies. You might consider any naturally-occurring instrument overtones to also be fundamental frequencies when you get to the point of considering how much distortion the electronics add.
... It had a single .1uf Mallory 150 white as the last coupling cap before the single 6V6 and I made a little quick switch rig so that I could blind A/B it ...
Maybe higher overall signal level helps highlight the differences. Say the cap adds 1/10th-percent distortion. A tenth-percent of 20vac could be more audible than a tenth-percent of 200mVac. I think I'll try switching either a late-stage coupling cap in the Valve Jr, or the coupling cap entering the phase inverter in the 5E3.
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Now that is a better description, and makes more of a case for spending the $ than any cap maker's marketing I've read. Nice to "see" ya again buddy!
Very glad to hear from you Dave!
Thanks for the hearty welcome gentlemen....I've been lurking with nothing to say for a while.
Keep in mind that this was a subtle difference, and I'm just giving a very un-scientific ear-only review.
We were in a quiet room (with soundboard walls) and very focused on the experiment, so I do feel it was valid.
Some of what I've read here explains the difference I was hearing when I was pushing the concept of parallel caps for better tone.
Thanks everyone for all contibutions to this thread.
"Do capacitors sound different?"
YES
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Thanks HBP
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This is Part #2 of the Musicap vs. OD experiement in my D'Mars ODS with 5879 in the overdrive. Refer to reply #78 & #80
Referring to Part #1 of the experiment, the coupling cap for V1a made a significant positive change in transparency and sustain. The post LTPI coupling caps did not make a significant change except perhaps a slight more transparent tone. I liked the Orange Drop PS series there about as well as the Musicaps. Closer to "just different & not better".
So for Part #2, I wanted to switch out the .1 cap that goes directly into the relay switching and bypasses the clean channel tone stack. Ironically, there was a yellow Mallory .1 in that position. So, I A/B'd the Mallory .1 vs. the Musicap .1 there back and forth for maybe 20 minutes playing single note leads, power chords, regular chording and fingerpicking chords. I did not have a Orange Drop PS that was .1 to try.
I liked both of them quite well! Honestly, I can't say the Musicap was "better" then the Mallory. The Musicap was more transparent in tone and had more sustain. However, the Mallory 150 had more of a vowel tone and some nice mid "grit" that was sort of a smooth sounding for grit.
I thought the Mallory 150 was every bit as good sounding in that one spot as the Musicap playing lead. However, I liked the Musicap more for playing chords & it did have a nice transparency that allows some of the nuances of playing to come thru a little better. So, the Musicap was left in.
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Next I tried changing the .01 Orange Drop PS after the first gain stage in the OD for a Musicap .01.
This made a significant difference also! Very nice change. I definitely prefer the Musicap .01 there much as a did using the .02 after V1a.
The Musicap (once again) had a MUCH smoother tone and more sustain and significantly better transparency. The improvement showed up the most in chording and it allowed some expressiveness in playing that the Orange Drop didn't have.
The smoothness was so much greater using the Musicap that I was able to lower the smoothing cap there from 390p to 120p and still have it smoother then the Orange Drop with the 390p. In fact, I think if I was playing out with a band, I might remove that smoothing cap altogether with the Musicap there. And ................ It was easy to tell that the Musicap also has more sustain then the Orange Drop PS cap.
This was definitely a keeper and worthwhile mod for me. So the Musicap stayed in.
I should add that I had the same impression about the Orange Drop having sort of a sharp attack with a note played & that the Musicap had a much warmer rounder attack to it. This stood out pretty easily in my listening. And I could see where someone else might prefer the sharper attack?
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Some of my conclusions so far.
The most significant improvement in transparency, sustain and smoothness was after the V1a coupling cap, .......... the next most improvement was after the first gain stage in the overdrive section coupling cap V2b with similar improvements in each of those categories.
I am thinking that changing the cap earlier in a clean or overdrive channel gives the greatest bang for the buck? Post LTPI coupling cap changes were different but not necessarily better. The .1 change was useful but not necessary.
There is a trade off for sure. The Musicap changes gave me more sustain, greater transparency/articulation and smoothness. The downside is that the "vowel tone" for single note leads is hardly there. But there is a musical sweetness and transparency that is a reasonably tradeoff and for me still an improvement. (the vowel tone I am referring to is sort of a smooth version of a notched wah wah pedal)
I think in a Tweed Overdrive Special, a Tweed BluezMeister or a D'Mars Overdrive that one could get a significant and noticeable tone improvement changing only two (perhaps 3) coupling caps. I think it could be one of the best $20-30 dollar investments in tone mods.
IF changing more caps continued to increase transparency, I do NOT think I would like an amp with all Musicaps. I am thinking about these Musicaps like a "flavoring" and not using them as the predominant caps in an amp.
With respect, Tubenit
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Silly question (will get me thrown out of the thread, how many tests do you want us to do?), but what if you put the two caps with the opposite characteristics in series in the same position (change of capacitance value aside or getting two caps twice the value). Do you get the worst of both or the best of both?
Just wondering if the caps are adding to the signal or the transparent ones letting what is already there through.
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wondering if the caps are adding to the signal or the transparent ones letting what is already there through
My best wild guess is the answer is yes to both of those.
I will tell you that I've paralleled caps for yrs and have found sometimes combining different types has been useful in "flavoring" the tone. And as I have mentioned before, I find mixing caps in different places to help achieve the tone I want. Don't know about caps in series?
I am very intrigued by Willabe's review of the Jupiter caps and may try those as the prominent cap when I do another build? Apparently they have some similar tone attributes to the Orange Drop PS/225. I am thinking about the Musicaps strictly as seasoning and not the main cap/s that I would build a tone base from.
With respect, Tubenit
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I got out my Heritage LP with Gibby HB's and played slide tuned to open E, fingers, no pick, mostly neck PUP, some with both PUP's, with both heavy ceramic (Mudslide/black) and glass slides for a good hour or 2.
Cap choices of what I liked changed completely. I was not expecting this at all. :dontknow: I'll try it again and write down some notes and post them.
Very surprised to find the amount of sustain with the Champ 5F1 set up in the bread board with my stand alone Fender Reverb in front and the WGS 15" alnico speaker. Any more sustain and I would say it was feed back.
It was really singing. I could hit a chord and easily slide it all the way up the neck, then shake it and it just kept ringing/singing, sounded just like a pedal steel player with a volume pedal but I didn't need the volume pedal. I could 'hang' a note, any note, a loonngggg time, great for slide. Volume set from 10:00 up to 2:00 with 5E3 tone control set at ~ 10:00 to 11:00. Guitar volume full up, guitar tone control mostly full up but sometimes rolled off of varying amounts to all the way fully rolled off.
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Talk about a "cliff hanger" ............... can't wait to hear the cap reviews playing slide!
I am going to make a wild guess and wonder if the less transparent caps sounded "better" for slide? And that may be totally incorrect? (I find for slide that sometimes a more muted and gritty tone sounds pretty cool.)
Also, I'd love to hear sound clips of your slide playing if you are ever inclined to share them! :thumbsup:
With respect, Tubenit
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Since you guys are in the capacitor type of mood can anybody tell me about these caps? Salvaged a few out of a trashed Wurlitzer organ.
(http://i406.photobucket.com/albums/pp142/printer2_photo/Guitar%20Amp%2002/wurlitzer%20caps_zpsgejoyfli.jpg)
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I am going to make a wild guess and wonder if the less transparent caps sounded "better" for slide? And that may be totally incorrect? (I find for slide that sometimes a more muted and gritty tone sounds pretty cool.)
No, the opposite, I liked the caps with less grit/artifacts. :dontknow: I was very surprised, I thought it would be pretty much the same in what I was hearing and liking/not liking from certain caps. Dirty slide can sound very good sometimes and I listen to recordings with slide like that but I like a smoother singing tone for me. (The blues guys talk about 'back in the ally/gut bucket' dirty blues, Hound Dog Taylor, as opposed to 'Up town' sophisticated blues, Bobby Blue Bland.)
I'll have to play more and see if I still like that cap the best.
I ended up playing with the 'new' Fender blue cap. Very clear, clean, less bottom end so a little more treble/but not really what I'd call chime. (Probably why I had to turn the amps tone control down to ~10:00 with the LP from ~2:00 with the Strat?) Sounded kinda dull/thin/flat/not 3D/no edge, so not very full sounding with my Strat. And my Strat is a rosewood fret board and the stock PUP's are full sounding not thin at all for a Strat. And I live on the neck PUP for lead with both guitars.
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I ended up playing with the 'new' Fender blue cap. Very clear, clean, less bottom end so a little more treble/but not really what I'd call chime. (Probably why I had to turn the amps tone control down to ~10:00 with the LP from ~2:00 with the Strat?) Sounded kinda dull/thin/flat/not 3D/no edge, so not very full sounding with my Strat
Brad, I can't tell from this if this is the cap you liked best with slide or simply one that you tried with playing slide?
Can you clarify please?
I've always like slide guitar. I was a fan of J B Hutto, Elmore James, Muddy Waters, & Hound Dog Taylor and play more in that sloppier style. Johnny Winter, Paul Black, Dave Hole and Sonny Landreth are probably my favorite players.
With respect, Tubenit
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I liked the 'new' Fender blue best with slide.
Played more last night and over all on the caps for slide the jury's still out. :dontknow:
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Any cap tone updates from anyone else????
I did some more experimenting today and found with .1 caps I prefer the regular Orange Drop's 715's that Doug sells over the OD PS series. The bass tone seems tighter. The PS cap was a tad smoother tonally but the deeper part of the bass notes seemed flubbier/fuzzier and less solid/bell like tone.
I only tried this in one spot in an OD channel. I "A/B'd" this back and forth quite a few times and feel like there was a distinct difference tone wise. I liked it better for chards, single note leads and finger picking chords. Sustain was also comparable to the Orange Drop PS.
I am thinking that on bass tones I prefer the clearest tight bass tone that I can get.
With respect, Tubenit
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I just replaced the tone caps in my AB763 with .022 musicaps, and I feel a difference. Seems to ring more. Clear, sharp, but smooth? I don't know? I had .022's in there before as well. Orange drops.
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I tried some Musicaps in the amp I am working on. The 5879 pre to the Marshall CF and KT66. BTW, I looked in my stash of parts and found a 6.6K multi-tap OT designed for KT66's. My findings are a Musicap destroys the Marshall Swirl when used in the first stage coupling. Used at the tonestack replacing the Aerovox .22 changes nothing. IMO not a good cap for a Marshall type amp.
I am installing these in a decade box. Switching to Mallorys (older stock yellow and older stock white that have the more rubbery feel) Retains a small amount of the true Marshall Clean. Xicon, Sozo Vintage Yellows and Philips Mustards all perform so closely that I would simply select either what I onhand or what I could get cheaper.
Still, I am back to NOS Aerovox all the way till the Phase Inverter. Here I am using Sozo yellows because I am preferring .33 and they are the only thing I have in that value. I tried 225 OD's and the amp felt stiff, but the initial attack was stronger as in the amp had more punch.
Next I plan to try the OD 225 in the first Coupling cap positions which are different that your normal Marshall since I am using the 5879 I am using a .1 coupler. I did like the punch from the OD 225 so I am hoping I can retain some of it there.
I am fairly sold on the Aerovox for the tonestack since I simply have a lot of them and have had very positive results with them. These are really older HiFi caps.
As so far as the "Marshall Crunch", this is limited by the use of the KT66 and plugged into a 4, 10's with 2 Weber 10A125/20 watt and 2 weber 10F125/30 watt all no dope and well broken in I am getting surprising cleans, but changing to my 2, 12 with Greenbacks it feels a little dirty.
Switching these speakers back and fourth with cap changing makes the mind a mess as it becomes very difficult to choose, but I am saddened the Musicap did not perform as I had high hopes. So I feel we are simply back to individual circuits and how each cap performs within that circuit.
OTOH, I did try the Musicap in my 5G9 and all I have to say is I have some more on order as they perform fabulous in this tweed, but please remember none of my amps end up being exactly like the schematic. What I am saying is if you have a 5G9 that is bone stock this review may not apply since I rarely use as large bypass caps so I am working with different frequencies.
I thought I would add some of my hearing tests to contribute, but I have to agree with Tubenit as I am finding similar results and I also wanted to contribute my findings with something different.
The difference in response is worth the time. I also parallel caps as well sometimes to a benefit, but not always. For instance a Parallel of a Yellow Sozo with an OD 715 not so good to me, but Jupiter Yellow with an OD 715 in a 5E7 Bandmaster is fabulous Darling. :icon_biggrin:
I have some of the Fender Caps coming from Angela and should arrive today. I have read a number of posts from builders liking these as couplers in preamps. They are not cheap tho. In this constant tone chasing sometimes I wish I could not hear things like diode switching cause :l2: then I could blow the money somewhere else.
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Since you guys are in the capacitor type of mood can anybody tell me about these caps? Salvaged a few out of a trashed Wurlitzer organ.
(http://i406.photobucket.com/albums/pp142/printer2_photo/Guitar%20Amp%2002/wurlitzer%20caps_zpsgejoyfli.jpg)
I don't really know anything about them, but I have used them. I have mentioned I build a lot of different preamps and I have some of these in 2 different Valco preamps, both Octal and I did not notice any what I refer to as choking like Orange caps seem to do to the older SE designs.
I will say that they seem to last as well as the blue molded Fender caps.
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Ed, I am very appreciative of your sharing your findings with the caps. Very thoughtful in your approach and in how you wrote up the experiment.
I can easily see MusiCaps being a poor match for Marshall tone, makes sense to me. And yet, they are proving to be somewhat useful in some limited specific places in other amps.
With respect, Tubenit
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Thanks Ed for posting your results! :icon_biggrin:
My findings are a Musicap destroys the Marshall Swirl when used in the first stage coupling.
.........but I am saddened the Musicap did not perform as I had high hopes. So I feel we are simply back to individual circuits and how each cap performs within that circuit.
This has been my suspicion all along, that there is no 1 single cap that's a '1 size (brand) fits all.'
OTOH, I did try the Musicap in my 5G9 and all I have to say is I have some more on order as they perform fabulous in this tweed, but please remember none of my amps end up being exactly like the schematic. What I am saying is if you have a 5G9 that is bone stock this review may not apply since I rarely use as large bypass caps so I am working with different frequencies.
Great, very good to know. :icon_biggrin:
What K bypass cap value are you using in the 5G9? I have a 6T rotary switch hooked up on the BB to the 1st gain stages K, with 1.- open/no cap, 2.- 0.68uF, 3.- 2.2uF, 4.- 4.7uF, 5.- 10uF, 6.- 25uF. I've not noticed any real difference in hearing the coupling caps any where I set the K bypass rotary switch.
I also parallel caps as well sometimes to a benefit, but not always. For instance a Parallel of a Yellow Sozo with an OD 715 not so good to me, but Jupiter Yellow with an OD 715 in a 5E7 Bandmaster is fabulous Darling. :icon_biggrin:
Oh, that is fabulous Darling. :l2:
I have some of the Fender Caps coming from Angela and should arrive today. I have read a number of posts from builders liking these as couplers in preamps.
I like those caps so far. Please let us know what you find/hear with them. :icon_biggrin:
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Thanks Ed for posting your results! :icon_biggrin:
My findings are a Musicap destroys the Marshall Swirl when used in the first stage coupling.
.........but I am saddened the Musicap did not perform as I had high hopes. So I feel we are simply back to individual circuits and how each cap performs within that circuit.
This has been my suspicion all along, that there is no 1 single cap that's a '1 size (brand) fits all.'
OTOH, I did try the Musicap in my 5G9 and all I have to say is I have some more on order as they perform fabulous in this tweed, but please remember none of my amps end up being exactly like the schematic. What I am saying is if you have a 5G9 that is bone stock this review may not apply since I rarely use as large bypass caps so I am working with different frequencies.
Great, very good to know. :icon_biggrin:
What K bypass cap value are you using in the 5G9? I have a 6T rotary switch hooked up on the BB to the 1st gain stages K, with 1.- open/no cap, 2.- 0.68uF, 3.- 2.2uF, 4.- 4.7uF, 5.- 10uF, 6.- 25uF. I've not noticed any real difference in hearing the coupling caps any where I set the K bypass rotary switch.
I also parallel caps as well sometimes to a benefit, but not always. For instance a Parallel of a Yellow Sozo with an OD 715 not so good to me, but Jupiter Yellow with an OD 715 in a 5E7 Bandmaster is fabulous Darling. :icon_biggrin:
Oh, that is fabulous Darling. :l2:
I have some of the Fender Caps coming from Angela and should arrive today. I have read a number of posts from builders liking these as couplers in preamps.
I like those caps so far. Please let us know what you find/hear with them. :icon_biggrin:
On the 5G9 and most other amps I normally have a 4.7 to 10uf at V1. In my 5G9 it is a 10uf. Further along the signal path I rarely get above 6.8. This is when building Tweed and Blackface types. In Marshall and similar higher gain amps there is no telling, but if I have large output tubes I will always use larger values as they will not get flabby.
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I put the musicaps in an AB763 tone stack, and coupling position. The preamp is the SMS Classic from Sarno Music Solutions in St. Louis. It's the Jerry Garcia version. I am going for very clear, bell like, chime and clarity, and the musicaps seem to have bettered the orange drops for this application. It is most certainly a situation dependent mod.
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Thanks for posting your results Searing. :icon_biggrin:
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With Dumblish inspired amps like the D'Mars, Tweed BluezMeister, & Tweed Overdrive Special, I have found that if I increase the coupling cap sized too much (especially in the overdrive channel) that the amp would start to sound fizzy/gritty/buzzy. I like a smooth tone that sustains and is very sweet musically. So, I was confined to sticking with the original size values.
However, I continue to find that these Musicaps are so transparent sounding, that I can significantly increase the size of the coupling caps and still have a smooth tone that is musically sweet and not have problems with grit/fizzy/buzzy side effects.
Today, I spent about 2 hrs A/B-ing caps in 3 different positions and found that I could double the size of the first coupling cap off of V1-1 for a richer yet smooth musical tone. AND ............ I could double the size of the first coupling cap after the first gain stage of the overdrive on my D'Mars also.
Increased .02 first coupling cap (clean channel) to .047. Increased .01 first gain stage (overdrive channel) to .02.
Bottom line is that I am getting the smoothest most musically sweet overdrive that I've gotten from any build I've attempted. Excellent sustain also!
Again, I do NOT think I would want these Musicaps thru out a guitar amp. However, I am finding a few here and there is really helping in finding the smoothness and transparency I want from my amp.
IF you are doing a D'Mars, TOS, or TBM build, ........... I would suggest trying two Musicaps. One in the clean channel in the signal path. And one after the first gain stage of the overdrive. They are expensive caps, but I am finding them to be worth it.
Just an FYI. With respect, Tubenit
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Very interesting. Thanks for posting your findings T. :icon_biggrin:
I'm close to getting my workshop cleaned up and re- organized, when I'm finished I'll put in the 2nd 12T rotary switch on the bread board for the 2nd gain stage coupling cap position on the Champ I have on there.
I'll my post findings soon. :icon_biggrin:
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OK, I did more extensive experiments today with the Musicaps.
Out of 9 caps in the signal path, 3 made a VERY significant improvement in transparency, musical tone and smoothness.
3 positions were just different. More transparent but less vowel tone. Simply a trade off. Maybe the Musicaps would be better in those positions
for rhythm and chording. But I prefer the vowel tone more of the Orange Drop PS in those positions.
3 positions were significantly negative tonally using Musicaps. Way too sterile. Very hifi-ish sounding. Transparent but not musical sweetness.
Some conclusions reviewed:
- Most dramatic results is in the first coupling cap
- IF you were going to use Musicaps, I'd try them most in the clean channel and early OD channel coupling cap positions
- In the post LTPI, they were just different. Same was true in clean channel tone stack.
- Certain positions they were somewhere between bad to awful
- I definitely would NOT build an entire guitar amp with Musicaps
Currently, I am thinking an amp like a D'Mars ODS or a Marshall might benefit from Musicaps in the first coupling cap position and maybe a few other places. But you'd need to try and A/B them for yourself to see. I probably would try the yellow Juptier caps that Doug carries every where else.
With respect, Tubenit
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I wonder why I'm not getting certain email notifications on replies for threads like this one? In any event, thanks for that spreadsheet to help clarify your findings tubenit. It helps greatly to see what you described in summing it all up like that.
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......... thanks for that spreadsheet to help clarify your findings tubenit. It helps greatly to see what you described in summing it all up like that.
Yes!
I probably would try the yellow Juptier caps that Doug carries every where else.
I forget if you've tried the yellow Juptier caps yet?
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I have not tried the yellow Jupiter caps yet. It's on the radar to try at some point.
Tubenit
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I like them so far but have only tried 1 in my bread board set up with a tweed champ, in the 1st coupling stage.
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Just wanted to let you guys know that I did a similar Musicaps mod to another D'Mars that uses 6V6's instead of 5881's.
Similar results. Smoother tone & more sustain and transparency. And I was able to increase the size of the coupling caps using Musicaps.
With respect, Tubenit
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OK, update. After hearing the D'Mars with 6V6's in a band mix on 3 different occasions with 3 different guitars being used, I think the Musicaps got it too "hi-fi-ish" in tone.
Some possible factors involved is that this D'Mars is in a zero volume stage setting and has a dummy load resistor with the signal going into a H&K Red Box cabinet simulator into a PA system.
However, I think the real issue is that I increased the value size of the caps when using the Musicaps? Bottom line, is that:
1) I returned all cap values back to the original design of the original D'Mars ODS
2) Returned all the OD channel caps to Orange Drops leaving the Musicaps only in the clean channel. This allowed the
clean channel to have remarkable transparency but allowed the Orange Drops in the OD channel to maintain some
warmth and vowel tone.
This seems to have resolved the issue.
I think these caps are reasonable choices for a transparent clean tone in the early gain stages but should be used sparingly in the OD channel or later gain stages.
with respect, Tubenit
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Some possible factors involved is that this D'Mars is in a zero volume stage setting and has a dummy load resistor with the signal going into a H&K Red Box cabinet simulator into a PA system.
I don't doubt what you heard/are hearing, but that set up is a different animal altogether. :dontknow:
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Brad,
When I first put the Musicaps in both the clean and OD of that 6V6 D'Mars ............. I listened to it thru a
cab with an Emminence Texas Heat and thought it sounded reasonably good & I liked it. I then listened to it thru an Emminence Pro Delta 12 and thought it sounded OK & still liked it but not quite as well.
But with the dummy load and RedBox into PA ............ too hi-fi sounding to me (and the main guitarist in the band).
With respect, Jeff
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I've got a set of Vitamin T Oils for coupling caps and Solen Fasts for cathode bypass to put in my neat final build of my D'Mars EL84 Quad. The amp is however way too loud for one room studio use, tube amps sound best when dimed, so motivation has been a bit low. Maybe I can contribute on this thread, so I'll get started tomorrow.
My thinking for using oils was that they would tend to damp higher harmonics of distortions and just add the lower "sweeter" harmonics and I was thinking the Solen Fasts would reduce negative feedback transients on the cathode bypasses, reducing any "ice picks", which the original Greenback Clone speaker really accentuated around 2 to 3 kHz. I have since replaced that Greenback clone with an Eminence Wizard and a Cannabis Rex which complement each other in several ways.
Maybe I'll just work on the clean channel with original MOSFET source follower and the PI. I have a full set of Oils, Solens, OD PS, OD 715s, OD 716s, Mallory 150 yellows and Mojo Dijons for the D'Mars, unfortunately I'm not very good at noticing subtle differences in sounds but will give it a go. Will see if Jupiters from Doug are within budget as well.
I believe the OD channel could benefit from smaller coupling caps going in to reduce thickness and mud in the overdrive harmonics and then some bass/low mid recovery with a TMB tone stack after the cathode follower, as has been mentioned in a different thread. They are both good areas to play round with various capacitor types.
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Yes, please let us know what your ears find. :icon_biggrin:
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Be sure to work out some form of switching capability, so you can hear the caps in quick succession. That will help address "confirmation bias" in which we tend to hear what we expect to hear.
Coupling caps will pop the first time they're switched (it's the cap charging to the applied voltage). After that, you should be able to switch with no popping.
Usually, very big differences (speaker change, large cap value change) are easy to hear even after some time delay. Subtle differences can be hard to hear, even if you can switch almost immediately.
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Duly noted HotBlue.
Well, that was really unexpected.
With 5 way switch I tried 150's, Mojotone Dijon, Orange PS, Industrial 2kv switching cap PP, and a VitaminT. In the coupling between input valve and stage 2. I had several of each so I measured them and chose the ones of closest value they were all 0.021 uF by my meter.
Had to have a lot of listens to actually get my ears around it but;
The 150, PS and industrial PP had a kind of indistinctness and harshness about them.
The Dijon and Vitamin T were much more transparent, think the Dijon might have had a tiny bit more warmth than the Vitamin T but the Vitamin T had a bit more top end sparkle.
In a way it was very subtle, but in another way it was rather gross and obvious. Three failed, two passed is how I would put it. To be fair one should probably take a larger small sample size than 1 unit.
A person could go insane trying to get every cap in an amp optimised so just in case, it's been nice knowing you folks.
Guess now I will shunt out the fails and try OD 715 and 716 with the winners.
Oh Dear Me !!! It appears I do not have 716's, thought I got them with the big order 8 months ago but nope.
The OD 715's were in the pass category, transparent and full bodied. To be honest the three "passes" all had something to distinguish them from the others but could not really say that any of the three were better than the others. My ears are probably fatigued by now.
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One HUGE difference.
Some of the more expensive caps have much better shielding. Doing an "earth end" test on a CRO, a typical cap has 6mV pp hum wrong way round and 2 mV pp right way round, fingers gripping the cap body. Solens have like 0.1mV pp wrong way around and 0.0mV pp (undetectable with my CRO) the right way round. Vitamin T's are similarly hum free but the outer shell is a metal can and connects directly to the earth end lead internally, no confusion there.
I also observed that different caps of same value from the same "not so expensive" manufacturer can have significantly different hum rejection.
Caps with significant shielding advantages are the obvious choice for any amp stage that has low signal strength such as the input stages.
I have the Vitamin T's so all my guitars are going to get tone control cap replacements. (I think they may be standard in PRS)
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Finally, Vitamin T, 715, Dijon and 150's in the two 0.01 uF couplers between PI and PA (via PPIMV). This amp stage has much different operating conditions than input stage, higher DC and a lot more signal strength.
There were some very subtle differences but really - no difference, not even enough to say I subjectively preferred one over the other, although I will go with the 715's here.
I think ones choice of size, shape, color and cost may be more significant factors. :icon_biggrin:
Rolling tubes gives a much greater variability in tone, in the past noticing major differences between 2 different 12AX7's from the same manufacturer, both new, and then choosing a 12AX7 from a different manufacturer.
Transformers also are known to give markedly different sounds, and whilst never having used them, a Classictone is on order for the final build OT.
It was a good exercise in listening vewy vewy carefully when hunting rabbits. In the end they all taste good as long as they don't have myxomatosis.
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Would be interesting to know what amp.
https://www.youtube.com/watch?v=XIaENqCBajY (https://www.youtube.com/watch?v=XIaENqCBajY)
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Found this last night when looking for something else. :icon_biggrin:
From Vacuum Tube Valley, issue 11, VTV Listens to Signal Capacitors, page 26;
"Some tips: Remember to wire signal capacitors so that the inner foil points toward the output and the outer foil points toward the input."
Ok, we got that, but then he writes;
"If you wire the outer foil to the output side, the sound will be muffled and rolled off."
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Printer 2,
THANKS for posting that! The Mallory 150's sounded muffled to me and I thought the Illinois caps had the best definition and articulation. Of course, that's simply my personal subjective review.
With respect, Tubenit
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Found this last night when looking for something else. :icon_biggrin:
From Vacuum Tube Valley, issue 11, VTV Listens to Signal Capacitors, page 26;
"If you wire the outer foil to the output side, the sound will be muffled and rolled off."
Hmmm...interesting to me. The reason being that after dragging a old amp i built years ago out of storage a few months back and tweaking it for the last few obsessively, at one point it started sounding amazing to the point i threw it back into the cab and stopped tweaking it. It had sounded bright and thin and i couldn't seem to get rid of that issue with any of the normal ways. And when i red the quote above it struck me because he only change i made between the point where it sounded bright and thin then great was i changed a tone stack cap. I was trying something and accidentally hit the cap with my iron and melted a rather deep hole in it so i changed it. After i did i started noticing the change and i couldn't imagine thats what did it but i could not think of anything else i did at the change in tone. And it wasn't because they varied in value because i have tried different values in the tone stack and it took a jump to double or 1/2 value to make a difference, and even then it never sounded like this whatever else i tried. Also, i had just installed all new caps of the same brand/value (mallory) because i was renewing the amp since the components were old and reused a zillion times. But after the renew the amp sounded no different. It was after i melted one of those new ones and swapped one of the old malories in that the change happened.
I still have a hard time believing it was that, but again i did nothing else i can remember between the change. My first thought when reading the above quote is that the tone caps in the stack were never oriented correctly (assuming this really CAN change tone) and when i installed the new caps one was but not the other. Then when i melted that one and swapped a old one in it went in oriented correctly. Then i stated thinking about how i never felt the tone stack was quite right. the way the treble and mid worked just seemed wrong. The treble got very thin and the tone turned to am radio sound when i turned it past about 2 oclock, and the mids were harsh turned up. And no, it wasn't a bad joint or anything like that because i was always redoing the solder joints as i experimented.
So what i'm wondering is, could there really be something to this orientation thing not just for noise but as far as tone, and could it be ultra important in the tone stack and possibly be one of the things that can make or break an amp? I can't see how or else production amps would be much more inconsistent than they are, but who knows. This makes me want to get the orientation in the rest of the amp right but the problem is, i have tried and b=never been able to hear it, at least not with mallory. I used the cable and cap from hot to ground then reverse it method. I never heard any change in noise when i'd reverse the leads.
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I've find this link
http://www.mennovanderveen.nl/nl/download/download_4.pdf (http://www.mennovanderveen.nl/nl/download/download_4.pdf)
Franco
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Hello. I realize this thread is over 120 days old and may qualify as "necro" but since my post here is exactly on topic and only creeps slightly into related topics, I figured I'd better try this first. I'd like to chat about what I think is another factor in how caps can alter sound in guitar amps, or really, any amp, and that factor is ESR, or Efffective or Equivalent Series Resistance.
First in the Power Supply - It is my understanding that ESR not only affects how much ripple is filtered out but also the "flexibility" in regards to the each stage's, and of course especially the power stage's, ease in swinging the power supplied. There is a term, in fact, for this characteristic, which is escaping my memory for the moment, but I imagine anyone who cares about such things already knows exactly to what I am referring - Power Supplies have an effective "impedance". Personally while I, like any vintage amp lover, enjoys a bit of "sag" I prefer to achieve it in other ways than poor filtering. This not only affects tonality and harmonic structure but also that enigmatic dynamic "feel" of guitar amps which are not reproduction devices but musical instruments in their own right.
Secondly, in the Signal Chain - Wherever possible I prefer non-polarized caps in the signal chain, even in bias resistor bypass caps, because polarized are non-symmetrical and this does have an effect on the waveform. I can see it to some degree even on an oscilloscope, to a larger degree on a spectrum analyzer or FFT, and I can hear it. It is somewhat slight especially if only one is swapped out for non-polarized as the effect seems to be somewhat cumulative. That last bit is actually anecdotal since I haven't been able to measure that other than by ear and that can be subjective.
Lastly, and tangential to ESR, is that it seems guitar amps, especially those that are overdriven and there even more especially those that seek to substantially overdrive the power section, sound sweeter if lower values are used early in gain staging coupling caps and get progressively larger as each step to the power section is considered. IOW "trebly" at the front and "bassy" further in.
I'd very much enjoy any comments on these concepts so thank you in advance for any hard data or even imaginative musing.
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i think the best capacitor is no add any signature to the sound but it never exist,,could you tell me which cap from all caps you had tested that add very little signature to sound?
thank you!
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caps by design will have some effect on tone since they interact with frequency. If it allows a large bandwidth to pass, you will hear more frequencies, narrow band will do the opposite. it's a math n experiment, repeat til happy kinda part :laugh:
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I like HotBluePlates' posts quite a lot because he actually does the work IRL not just imagining or regurgitating others' imaginings. I fully agree from my own work of many decades that in the majority of cases, cap values have far more tonal impact than cap materials with one possible exception - Cathode Bypass Caps.
A very long time ago I read that electrolytic caps are asymmetrical in ESR and wondered, especially since a bypass cap heavily influences/controls gain (actually amplifying small differences) so I tried replacing bypass caps with true non-polarized versions where possible and reversed back-to-back (series) electrolytic caps where more practical. I actually expected more difference than I could measure or hear but there IS a difference and it is cumulative depending a lot on how many stages in the signal path have bypassed cathode design.
This difference naturally increases with gain influencing whether any overdriven clipping is symmetrical or asymmetrical, with obvious and well documented differences in harmonic generation.. That effect can be reduced if there are subsequent stages that reverse the asymmetry. Bottom line is there is considerable difference when overdriven and all gain stages are either 100% symmetrical or 100% asymmetrical rather than a mix.
It doesn't take a great deal of effort to try this for yourself and most gain stages will have full frequency response gain with 1uf-2uf non-polarized caps so it can be tried with no electrolytics at all fairly easily and cheaply.
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Hello enorbet2, an old thread for sure but findings and/or updates are always appreciated. Since this time I have included a few options to help with what I think is what you're describing with "symmetry of gain" and in the power supply fitration as well. Of course we are talking about small details but these can and do make slight differences in gain, character, sound, possibly limiting/eliminating artifacts and parasitic oscillations. Also, these additional caps on cathode bypassing may be another option yielding similar results to using non-polarized larger caps alone? Attached are a few examples I have incorporated. Tubenit has experimented a lot with capacitor use in many places of the circuits and not only in the manner with which you have commented but if you haven't seen the files called "smoothing caps" you might find it interesting? But, I have not done everything in one amp all at once and don't think there would be this need? But who knows, you might just want to try it all? YMMV as they say. :)
jojo