Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Leevi on March 03, 2014, 01:55:46 pm
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Any tips how to make the distortion (overdrive) more sustainable e.g. in 5E3?
/Leevi
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You mean to make a distortion that causes the amp to sustain (hold a note) longer?
More sustain = more compression, and when you get that as a result of distortion, then more compression = more distortion.
Look at the image below, mainly #1 and #3. For the heavily-clipped #3 to finish sustaining and sound like its volume is decaying, the original unclipped wave (#1) would have to decay until its peak amplitude is lower than the flat-top of the clipped signal. So you clip the plain signal heavily in order to get the sustain effect.
So if you want to make a 5E3 sustain longer, you need to add gain stages or diode-bounding distortion circuits. In other words, make it a high-gain amp instead of a 5E3.
Or get a distortion pedal, which is probably a better choice (and more easily changed or reversed).
(http://www.cubisteffects.com/images/MIY/Pt2DiodeSymmetry.jpg)
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Put a boost pedal in front of it.
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maybe a compressor pedal? I just watched a youtube video(i think it was called kings of tone: david gilmour) Showed demenostrated and explained compressors a bit.
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You'll laugh but reverb helps a lot.
Brad :icon_biggrin:
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You mean to make a distortion that causes the amp to sustain (hold a note) longer?
Yes
So if you want to make a 5E3 sustain longer, you need to add gain stages or diode-bounding distortion circuits. In other words, make it a high-gain amp instead of a 5E3.
I refer to the link below where is a demo of Tungsten Cream Wheat which is a modification of 5E3 without extra gain stages.
This is what I'm looking for.
Crema Wheat & LSL Tbone (http://www.youtube.com/watch?v=wkLbm06IFH4#ws)
/Leevi
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I think he has a delay pedal and maybe an overdrive pedal with that demo? Sure sounds like a delay to me. I'm willing to bet that Carbon Copy delay and something like a ZenDrive would come very very close to that.
IF he didn't use a delay pedal, then I'm thinking that he added delay in the mix? If you listen carefully, there is a echo or delay behind the notes. Delay obviously will add quite a bit of sustain to an amp.
With respect, Tubenit
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I think he has a delay pedal and maybe an overdrive pedal with that demo? Sure sounds like a delay to me.
I think you are right.
/Leevi
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Look at the image below, mainly #1 and #3. For the heavily-clipped #3 to finish sustaining and sound like its volume is decaying, the original unclipped wave (#1) would have to decay until its peak amplitude is lower than the flat-top of the clipped signal. So you clip the plain signal heavily in order to get the sustain effect.
I didn't get how a normal diode could work like that, they must be zener diodes or?
/Leevi
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I didn't get how a normal diode could work like that, they must be zener diodes or?
A normal diode has a forward bias voltage. For silicon diodes that voltage is typically about .7v. So, a single diode placed across the signal path will conduct whenever the voltage reaches or exceeds .7v. This will clip the signal voltage to .7v for half the signal. Use two back to back diodes to clip positive and negative peaks of the signal to .7v (actually 1.4Vpp.
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That LSL Tbone is apparently a really nice guitar with hand-wound pickups, like over 2 grand so it probably has monster sustain on its own. It also says in the video he has both vol and tone cranked to 11. If neither of these things help try a sparkledrive. Hope this helps!
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A normal diode has a forward bias voltage. For silicon diodes that voltage is typically about .7v. So, a single diode placed across the signal path will conduct whenever the voltage reaches or exceeds .7v. This will clip the signal voltage to .7v for half the signal. Use two back to back diodes to clip positive and negative peaks of the signal to .7v (actually 1.4Vpp.
I agree. I thought that the clipping voltage is higher in the figures.
/Leevi
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I agree. I thought that the clipping voltage is higher in the figures.
I didn't see any reference to voltage levels in the figures.
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I didn't see any reference to voltage levels in the figures.
I don't see either, it was just my assumption.
/Leevi
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I added some modification proposals to 5E3 in order to increase gain.
What do you think about them?
/Leevi
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What the guy is playing, starting at 0:25, sounds like a 5E3 all the way up to me.
The sustain I hear at that point on is mostly:
- his playing of open strings
- varying his touch to play loud & soft, but that mostly comes out as "distorted" & "cleaner"
The other mess being played prior to 0:25 and after 2:40 is not the same amp/sound. I also think I hear faint reverb/delay like Tubenit said when listening through headphones, as there's a slapback in the right speaker and more ambience than you'd get with a single mic tight against the grille as shown in the video.
Mostly, this sounds like playing style to me. Tubenit can tell you there are times I can play a Tele through a dry amp and sound almost like I have a faint reverb going (if you consciously avoid muting strings).
I added some modification proposals to 5E3 in order to increase gain. What do you think about them?
Do you already have a 5E3 style amp built?
What you have shown should increase gain a little, but you never know for sure if it will be what you want until you build/tweak the amp. I'd especially ecommend som kind of substitution box for changing plate & cathode resistors to quickly hear what change they're making.
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In the clip you posted it shows the tube chart in the amp and it's 12AX7's for pre and PI. The clip says 5U4 and GZ34 not 5E3 for rectifier tube.
I did a search for that amp and a few guys said he has the 2 channels wired up differently so their separated and the volume controls are not interactive. They said its like a Mission amps volume control mod that they sell but I could not find exactly what that is at the mission amps web site.
Brad :icon_biggrin:
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I did a search for that amp and a few guys said he has the 2 channels wired up differently so their separated and the volume controls are not interactive. They said its like a Mission amps volume control mod that they sell but I could not find exactly what that is at the mission amps web site.
Based on Willabe's post, I searched for Mission Amps 5E3, and I found this:
http://www.blueguitar.org/new/schem/blue_gtr/5e3modhi.jpg (http://www.blueguitar.org/new/schem/blue_gtr/5e3modhi.jpg)
and this:
http://www.privatepollution.com/images/Mission%20Layout.jpg (http://www.privatepollution.com/images/Mission%20Layout.jpg)
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Do you already have a 5E3 style amp built?
I have built several 5E3 amps but never made these changes since
the amp and its circuit is kept like an icon.
Currently I don't have 5E3 available in order to do tests.
/Leevi
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Tubenit can tell you there are times I can play a Tele through a dry amp and sound almost like I have a faint reverb going (if you consciously avoid muting strings).
That is absolutely correct! Lots of fun listening to HBP play.
With respect, Tubenit
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I built this and it will really scream. Sort of what SG posted, but with cap values more humbucker friendly. I have Celestion Blue in it and I have to say I really like it. It will do clean and nasty.
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Ed, do you know if there is a schematic available?
/Leevi
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I did a search for that amp and a few guys said he has the 2 channels wired up differently so their separated and the volume controls are not interactive. They said its like a Mission amps volume control mod that they sell but I could not find exactly what that is at the mission amps web site.
Yes, I have built couple of Crema Wheat variant of 5E3. The channels are separated from each other and the tone is implemented by using a dual pot with different cap values.
/Leevi
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Ed, do you know if there is a schematic available?
/Leevi
No schematic I know of. I printed this and if you look closely, I used white out where I changed values. It should not be difficult to revise and 5E3 schematic to match it. Actually, I did not use this layout. I got one from Sluckey and used that with these values. I do not have that schematic on this computer or I would post it.
I used the stock chrome chassis and made a pine cabinet. Really an easy build, I added the "Trick Switch" after as a mod instead of building it at the same time as I was not sure I would like it. I love it, but everyone is different.
I bet Sluckey will send you the PDF if you want, or if you have Visio you can edit the one he has. His layout is Hoffman style, but I did elevate the heaters as the PT I used had a CT for the heaters.
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I agree with HBP. A 5E3 cranked. He's got a good amount of mic distortion going on in that recording, hope you're not confusing that with sustain. I have tried a few of the Tungsten amps and they are excellent, but expensive.
Some sustain comes from playing style as well. Jeff Beck gets his schweet sustain through his finger picking style and his amp turned to 11 (because it's 1 louder than 10). Spinal Tap - "These go to eleven...." (http://www.youtube.com/watch?v=4xgx4k83zzc#ws)