Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Willabe on June 06, 2012, 12:18:40 pm
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(Edit; Schemo drawing is in reply #3 and layout drawing is in reply #7.)
I'm finally ready to start to solder this amp up.
This is my 2'nd try at this amp. I had traded with our friend tubeswell for a chassis and it did not go as planed. But I did gain some more needed experience working with and drilling metal. Got to break some eggs to make an omelet. :laugh:
The 1'st version had a ton of extra stuff ( PS, sag control, tube FX loop, ect....) I was going to put in, but it was too much in not a big enough chassis and I was _never_ going to get the face plate to line up with the chassis holes. (Sorry Pete, I know you tried to tell me. :w2: )
Then I read a post from our friend stingray 65 on how he uses inkscape, which is a graphics artists vector program, to design his face plates and sends it to a an engraver to make it. Then he uses double stick tape to fasten it to the chassis and then drills the pilot holes in the chassis and face plates at the same time.
When I read that the light bulb turned on above my head. :think1:
So I did the same and it turned out great, thanks Ray!
Here's some pics and I'll post more as I go.
The chassis is a blank 18 watt I got from mojo a few years ago. I'm going to build a cab for it too.
Face plate is black with white lettering, blue chicken head knobs and a blue jewel pilot light. I think it looks pretty good.
Brad :icon_biggrin:
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Here's 2 more showing the bias/balance pots.
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Looks awesome.Is the balance pot for the heaters or a bias balance?
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Looks awesome.Is the balance pot for the heaters or a bias balance?
Thanks cbass. :icon_biggrin:
It's for bias balance. 1 is balance and the other is for the bias range. There 25KL locking pots, I got them from Weber.
Doh, I for got to post the schemo drawing. :w2:
The B+ dropping R's have to be adjusted, their not all going to be 1K's.
Brad
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That is nifty looking. Interesting tube layout with the two different planes. I like it.
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Thanks Tyrannocaster,
I moved the PI and trem tube to put them by their associated controls. The tube spec sheets say they can be mounted it any position, so it should be fine. I might have to add a couple of vents to the cab. The chassis will be mounted like tweed combos.
I have to fix a few things on the layout drawing after which I'll post it and you'll see what/why I put the 2 tubes where I did.
Brad :icon_biggrin:
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Way cool and very clever layout! Layouts can really showcase a person's creativity.
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Thanks desalvo,
The layout I did has to do with trying to go with my interpretation of KOC's galactic wired ground and Merlins wired ground.
Every B+ filter cap is put close to the circuitry it's feeding and all of those grounds are brought together to it's filter cap's ground as a ground star node.
Here's the layout drawing. All jacks are insulated/isolated from the chassis. I'll note that on the layout drawing and repost it.
Brad :icon_biggrin:
Edit; Speed pot connection is wrong, wiper does not go to ground, X end of speed pot goes to ground on trem. FSW. I'll fix this and repost.
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bad ass
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I m guessing that, seeing how carefully you've done everything, this thing is going to sound great. I hope you can post some sound files. I love 6V6 amps...and EL84 variants, too. Do you have any idea how long it's likely to take for this to get to a playable stage? I know it takes me forever to do build one from scratch, and mine aren't as nice as yours.
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Thanks Tyrannocaster,
It's really still, what 95% a 5G9, so it should sound much the same as a 5G9, just (maybe) a little quieter.
All I did was to redo the layout with a wired star (galactic) ground and to add a few B+ filter caps, put in -bias/balance and added a dcv stand-off for the heaters. Oh and a circuit ground lift that I've been wanting to try.
As far as getting it finished, I'm pretty slow. :laugh:
I bought the iron, Merc. Mags. 3, 4 years ago because I wanted to hear the difference between it and a 5Y3 because of the changed PI and the grid -bias. I also need to make a cab for it, it will be mounted tweed combo style, so it's gonna be a while.
But since then I've come to realize that for _years_ I had been listening to recordings with this output stage -bias vary tremolo and really love it for certain things/guitar parts.
Here's a u-tube clip from Delbert McClinton at the CMA's and the guy playing the white strat is playin through a 5G9, I love it! Starts about 1 minuite in.
http://youtu.be/5TlaDUHMcfA (http://youtu.be/5TlaDUHMcfA)
Brad :icon_biggrin:
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:icon_biggrin: nice work!
--DL
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Thanks desalvo,
The layout I did has to do with trying to go with my interpretation of KOC's galactic wired ground and Merlins wired ground.
Every B+ filter cap is put close to the circuitry it's feeding and all of those grounds are brought together to it's filter cap's ground as a ground star node.
Here's the layout drawing.
Brad :icon_biggrin:
I follow your bias/balance much better in layout mode. You have 2, 22k's in series feeding the balance and from the balance wiper to the bias wiper you have another. The range pot is easy to understand. How did you come up with 22k values? What type of range are you expecting?
Also, I noticed you are running your CT to pin 5, then to your cap ground to yet another cap, then tied into the bias after the diode and 470. What is the purpose?
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Thanks DL. This is my 1'st complete scratch build _including_ the chassis and face/rear plate and layout.
I follow your bias/balance much better in layout mode. You have 2, 22k's in series feeding the balance and from the balance wiper to the bias wiper you have another. The range pot is easy to understand. How did you come up with 22k values? What type of range are you expecting?
The 1'st pair of 22K R's are in parallel that are feeding the opposite ends of the balance pot. It's to give the balance pot something to work against, if you leave them out the balance pot wont work. Their junction is feed from the term intensity pots wiper. If this amp didn't have the -bias vary trem this junction would be feed from the raw -bias.
The 3'rd 22K going from the bias balance pots wiper to 1 end of the -bias range is there to make sure there is always some -bias left even if you turn it all the way down. If you need more -bias you can make this R larger since it's in series with range pot and it's the
-bias path to ground.
Note that the way the the bias/balance is wired up, if either the balance pots wiper or the range pots wiper ever lifts (stops working) -bias will remain as a safety.
I think I need to see if I can add a -bias safety R to the term intensity pot in case it's wiper ever goes wonky. Not sure if you can or if you need 1 or 2 safety R's?
The values for the R's and pots for the bias/balance are from KOC's TUT books. There what he likes to use and IIRC it's for the overall impedance of the -bias supply, to keep it low?
For the -bias range, the Fender schemo calls for -28dcv (the PT has a 60v bias tap), so with 25%, +/-, I'll need to go from -21dcv to -35dcv. But since this is a bias vary term that range might not be enough to let the term over come the -bias of the output tubes?
Also, I noticed you are running your CT to pin 5, then to your cap ground to yet another cap, then tied into the bias after the diode and 470. What is the purpose?
The B+ CT is going to pin 5 so I can twist all 3 B+ PT HT secondary wires together (I'm using it as a solder post), to help cut down on the electrostatic and electromagnetic field radiated from them, ie, noise, + now I have a ground wire to twist with the rectified B+ wire from pin 8 of the rectifier tubes socket (for the same reason) to the 1'st 2 HT B+ filter caps, 22uF each in parallel @450v = 44 uF @ 450v.
The 1'st -bias caps ground is tied to the B+ HT CT and 1'st pair of HT B+ filter caps ground because the -bias comes from a tap on the B+ wind, so any noise from the HT B+ filter caps charging current on the HT B+ is _also_ on the -bias tap. This also lets me run this ground wire with the -bias tap wire as a twisted pair, for the same reason stated above. This is a very noisy ground and KOC, Merlin and others wire it up this way. These grounds go together as their own ground star node _only_ and _then_ they run a wire to the next ground star node and so on. If this PT had a CT on the heater wind it would go there too. This is so the B+ filter caps charging current circulate by themselves and do not affect other circuits by modulating their grounds.
The 2'nd -bias caps ground goes to the screen ground star node to separate it from the HT B+ ground star nodes charging currents noise.
I'm trying to use twisted pairs or twist 3 when/where ever I can, some guys don't and their very happy with their amp builds.
There is 1 hitch in the giddy up with this. If I'm getting this right, KOC likes twisting wires to cancel noise and IIRC, Merlin says to keep the B+'s ground rail wire _away_ from the B+'s positive rail wire, so the ground wires noise is not induced back into the B+ (positive) rail. :w2: :laugh:
Again this is just my understanding/interpretation of KOC's and Merlins wired ground star/node scheme. Different guys wire their amps ground differently with good/great results, no doubt.
Our host Doug has his own grounding scheme that _many_ guys here have used on _many_ amps and report great results.
Any and all corrections of what I'm saying are welcome.
Brad :icon_biggrin:
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I have 2/3 of the amp wired up and it's going well so far.
But I lost the spec. sheet for the PT and OT, so I don't know what/where all the wires/colors should go.
I measured both for resistance and got these for readings;
PT primary, 2 Black
Secondary;
2 Red, 2 Yellow, 2 Green, 1 White/Red, 1 Black/Red
Red/Red=118 ohm
Red 1 to Black/Red= 58.2 ohm
Red 2 to Black/Red= 61.7 ohm
Red 1 to White/Red= 48.5 ohm
Red 2 to White/Red= 71.3 ohm
White/Red to Black/Red= 11.6 ohm
From these readings I gather that, R/R= B+ HT, BLK/RD= CT, WHT/RD= bias tap?
So I hooked up the PT temporarily, I get continuity on the grounds (CT, chassis safety ground and chassis circuit ground) 2 Greens=6.8vac unloaded, with NOS 5U4 plugged in to rec. tube socket, 2 Yellows on pins 2&8= 38vac, pin 8/2= pin 8= 413vdc no B+ filter caps/no load, reds on pins 4/5= 354.3vac, W/R= 58.7vac.
I take it pin 8's vdc are high because, 1 it's unloaded and 2 there's no B+ filter caps hooked up?
Is this also why I'm getting 38vac on pins 8/2 to ground?
OT pri. Brown, Green and Orange.
Brn. to Grn.=665.0 ohm
Brn. to ORG.= 48.8 ohm
Grn. to ORG.= 309.3 ohm
So ORG. is the CT, Grn. is the start and BRN. is the finish?
Thanks Brad :icon_biggrin:
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I take it pin 8's vdc are high because, 1 it's unloaded and 2 there's no B+ filter caps hooked up?
Is this also why I'm getting 38vac on pins 8/2 to ground?
Pin 8's vdc is not high. It's low because there is no cap to charge to the peak of the positive pulses. With a 354-0-354 PT, the unloaded B+ will be 500v with a cap.
Just ignore the 38vac readings on pins 8/2 to ground. Your meter is confused by the dc pulses.
OT pri. Brown, Green and Orange.
Brn. to Grn.=665.0 ohm
Brn. to ORG.= 48.8 ohm
Grn. to ORG.= 309.3 ohm
So ORG. is the CT, Grn. is the start and BRN. is the finish?
Check those again. Something is amiss. If BRN to ORG is 48, and GRN to ORG is 309, then BRN to GRN cannot be 665.
End1 to CT plus End2 to CT must equal End1 to End2.
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Doh! I forgot the 3. :laugh:
BRN to ORG.=348.8 ohm
GRN. to BRN.= 665 ohm
GRN. to ORG.= 309.3 ohm
So I take it the GRN. to ORG. is the start and BRN. to ORG. would be the finish?
Pin 8's vdc is not high. It's low because there is no cap to charge to the peak of the positive pulses. With a 354-0-354 PT, the unloaded B+ will be 500v with a cap.
Well that's a problem because 5G9 Fender schemo says 370vdc to OT CT. The iron set is Merc. Mags. so they should be right.
Brad :icon_biggrin:
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PT; based on your readings and guess-work:
2 yellow are 5V for recto filament; tie 1 yellow to pin 8 and the other 1 yellow to pin 2; tie pin 8 to the first filter.
2 red & black/red are for B+ recto; black/red is CT and grounded; tie red 1 to pin 4, tie red 2 to pin 6 of recto tube.
red/white is bias tap to bias PS.
2 green are 6.3V for filaments.
measurements of your OT are waaaaay wonky to be a push-pull type... is it possibly a SE type with a UL tap? you should read not more than 10% difference of DC resistance from CT to each end of the winding of the primary. most modern OT are wound to much closer than that, as in usually <5% diff.
--DL
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ORG is the CT.
--DL
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Thanks DL.
That's what I thought.
Brad :icon_biggrin:
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Just ignore the 38vac readings on pins 8/2 to ground. Your meter is confused by the dc pulses.
Ok, I thought it was because of having no B+ filter cap hooked up.
Thanks, Brad :icon_biggrin:
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Well that's a problem because 5G9 Fender schemo says 370vdc to OT CT. The iron set is Merc. Mags. so they should be right
Remember, 500vdc is unloaded. As soon as you connect it to the output tubes the B+ will drop. The amount of drop depends upon how hot you bias the tubes, rectifier tube drop, and PT internal resistance. You may be right on the money in the end, although I'll bet a cup of coffee that the B+ will be higher than you like. :icon_biggrin:
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Ok, thanks sluckey.
I'll just keep going then, the rec. tube is 5U4.
Brad :icon_biggrin:
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Ok, got some more soldered up. Not too bad.
Here's a pic, I'll try and finish up tomorrow, if so, then I can make my git'tar with tremolo go, WA WA WA WA WA...... :laugh:
If anyone see's any problems, please let me know.
Thanks, Brad :icon_biggrin:
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That looks good. Buss wire?
With respect, Tubenit
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Hi Tubenit, and thanks
The yellow/purple twisted pair goes from the PI's plate R's to the output tubes coupling caps. (if that's what your asking? :dontknow:)
Layout and schemo are in reply #'s 3,7.
Brad :icon_biggrin:
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I apologize. I didn't read all the posts. I was referring to a buss wire for grounding ala Hoffman's grounding scheme. I see you are using a different approach .....
I like the wiring and layout in your chassis. Very nice.
With respect, Tubenit
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Won't be long now. I am in a hurry for you. I want to see how your bias works out. I've got a bet it is better than dual bias. I am going the dual bias method, but I did get the mini 25kl pots so if yours is best I can copy. :headbang:
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Kool Project! I watched the vidio and man! what a top notch tremolo sound. I'm a big fan of tremolo and work it into songs as much as possible where is fits well. It fits real well on that song.
Your layout is new thinking for sure and looks so clean in appearance. Like a nice hot rod bike without a lot of clutter. I'm not familiar with that 5G9 model--will have to do some research on it.
Great Work! Looking forward to the first test run. Plate
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I was referring to a buss wire for grounding ala Hoffman's grounding scheme. I see you are using a different approach .....
I just realized what you meant, the B+/- rails are under the board as twisted pairs. There's a pic of the under side of the eyelet board in the 1'st post. I'm _trying_ to use KOC's and Merlins wired grounding.
I like the wiring and layout in your chassis. Very nice.
Thanks, I felt that my weakest area in amp building was was layout and lead dress. So I spent the last year and half or so working on it. I spent a _lot_ of time with SCH express and blank chassis, parts and rulers. :laugh:
This is my 3'rd scratch eyelet board and I'm still making layout mistakes that I don't see until I wire it up. :BangHead: :l2:
I might be chasing my tail with this though? I still need to think about it some more.
I want to see how your bias works out. I've got a bet it is better than dual bias.
Someone here said a while back that bias/balance was easier to adjust, but I don't really know.
I watched the video and man! what a top notch tremolo sound. It fits real well on that song.
Wa Wa Wa Wa Wa Wa, yep. That's why, for fun, I named it the Tremolator, . :laugh: IMO, it makes that song, without it, it would be missing something.
I think they sound great on ballads and 3/4 time songs too.
Our NZ friend tubeswell loves these bias vary tremolo amps . He kinda woke me up to their sound. (Thanks Pete)
Your layout is new thinking for sure and looks so clean in appearance. Great Work!
Thanks, but there's many very creative guys here and on other forums. But I think I'm starting to get the hang of it? :think1:
Looking forward to the first test run.
Me too. :laugh:
Brad :icon_biggrin:
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Well I finished soldering it up and no smoke, bias works fine, popped in tubes, set bias to 35mA's each tube, plugged in guitar and she sounds fine.
Next tried tremolo and nothing. :BangHead: :laugh:
Re-checked wiring and I believe it's wired up correctly.
Measured all the R's, fine, caps were measured when I 1'st put them in.
Tried 3 different 12AX7's, nothin.
Re-biased tubes down to 20mA's each, nothing.
I can hear it _very_ faintly.
Here's the trem tubes dcv;
Driver/CF
Plate, pin 1+ 410vdc
Grid, pin 2= 270.4vdc
Cathode, pin 3= 272.4vdc
OSC
Plate, pin 6 =270.4vdc
Cathode, pin 8= 2.06vdc
When I turn up the Depth control pot the amp gets louder, wither the trem FTS is on or off. :think1:
Seems alright, should I try changing the CF's 220K KR to 470K or make the 1M after the .1 cap from the K smaller, say 470K?
Vibroverb 6G16 is set up with 470K and 470K.
Brad :dontknow:
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This is why I won't attempt another tremolo amp without help from somebody...like this forum. :laugh: About half of the trem amps I have built have had real problems and a couple of them never did get the trem circuit working. They are tricky little buggers! Your amp looks great; once again, I wish mine looked that good. Really nice work.
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Thanks T,
The guys will set me straight and get my little amp to wiggle. :laugh:
Really the whole point of building this amp is for the tremolo, I gotta have it, got that sound in my ears and head. :l2:
I've seen/read about this here before and IIRC one of the fixes is to up the CF KR.
But well see.
Brad :icon_biggrin:
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Make the oscillator work first. If it ain't oscillating the plate will be a steady voltage. If it's working the plate voltage will be jumping all over the place. Same with the CF grid and cathode. You don't need a footswitch plugged in for this to work.
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OK, thanks Sluckey.
I'll go measure right now.
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Meh! She no wanna wiggle. :laugh:
I went over the scheme and my layout again and I still think there correct.
I changed the 3 osc. caps and used a heat sink this time, nothin.
I'll fool with it some more tomorrow. I think I'll try changing the term tube socket also.
(BTW Sluckey, I owe you a cup of coffee, 401vdc on pin 8 of the rec. tube, full load, you like cream/sugar or with N.O. chicory and a Beinye? {I'm sure I spelled that wrong.} :laugh: )
Thanks, Brad :think1:
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Got to be a wiring error in the LFO stage methinks.
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Hey Pete,
Me thinks your right, but I've been over it, again and again and again, but I'll check it again. :laugh:
I did figure out that I wired the 3MRA speed pot wired backwards, O to X, but that should only make the speed control work backwards?
I'm gonna futz with it tomorrow and see what happens.
Hey, take a look at reply #10 of the u-tube link to Delbert McClinton at the CMAs with his gitar man (white Strat) playing through an old 5G9.
Starts about 1 minute in. In the beginning and in the performance you can see (only for a few seconds a couple of times) an old tweed amp, looks like a 5G9 tweed, 1-12 combo to me.
What you think? I love it! That's the sound I want!
Thanks, Brad :icon_biggrin:
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What's the value of that resistor on the trem socket, pin 1 to 6? Measure it. Should be 100KΩ. If it's a 3 band color code it should be brown/black/yellow. If it's a 4 band color code it should be brown/black/black/orange. I don't see any yellow or orange. Post a closeup pic of the trem area,,,, socket, pot, footswitch jack, board.
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(BTW Sluckey, I owe you a cup of coffee, 401vdc on pin 8 of the rec. tube, full load, you like cream/sugar or with N.O. chicory and a Beinye? {I'm sure I spelled that wrong.} :laugh: )
Beignet, LOL.
I'm watching this one with interest. My 5E5 is coming along slowly and I am planning to add a trem circuit to it once it is working properly. But this time I'm doing the entire amp first and then putting in a small secondary board with the tremolo on it and until then there will be one unused 12AX7. I love tremolo; reverb makes no sense on a tweed amp (it sounds like crap in front of the distortion IMO), but you have to have tremolo! I just wish they weren't so finicky.
The tremolo I have in my 18 watt Marshall Lite is from the Matchless Hurricane (uses 1/2 12AX7) - it's a bias vary circuit and it's especially cool because of the way its effect gets overpowered when you push the amp, meaning you can hit a big dirty chord and it will start off with no tremolo and then the trem fades in; I LOVE this effect but was totally unable to get the circuit to work in the other amp I tried it in and it has an identical power amp. :BangHead:
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They say absense makes the heart grow fonder---when Mr. Wiggle does show up, it will be celibration time. Maybe when you check the resistor Sluckey pointed out---maybe that will be it! I'll be checking back in for the Victory Shout!
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Thanks guys,
Looks like ,Brown/Black/Black/Orange/Brown? It's hard to see these 1/2w MF's.
I measured all the R's as I put them in because of that, but it looks like I messed up?
I'll put in a CC 100K that I can read.
I killed my meters R/C functions last night. :w2: It was a 15 years (?) old RS, think I got my $$ worth out of it.
Brad :think1:
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Looks like ,Brown/Black/Black/Orange/Brown?
That's correct. The last color is probably gold.
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Wait, you said a few posts back, brown/black/yellow?
Brad :dontknow:
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read it one more time
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Ok, I see it now.
I'll post a few close-ups latter today. I'm wondering if I got a bum socket?
Thanks, Brad :laugh:
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Here's some close ups.
Some of the over head wires are out of place right now, I'll move them back in place once I get the trem working.
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You have a footswitch jack. Insert a footswitch, or connect an alligator jumper from the hot lug to the ground lug.
Work now?
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Here's more.
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More. I snipped out the 100K from the socket this morning to see the color code. I broke the socket last night on the outside edge behind pin 7. :w2:
Thanks, Brad :icon_biggrin:
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1 more, kinda blurry and my meter that I killed the R/C functions on last night. But it seems to still read voltages fine.
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You have a footswitch jack. Insert a footswitch, or connect an alligator jumper from the hot lug to the ground lug.
Work now?
Hi HBP,
Thanks, I tried that last night with the FTS and no go.
Brad :dontknow:
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Insert a footswitch, or connect an alligator jumper from the hot lug to the ground lug.
That will kill the trem on this amp.
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Here's the layout drawing and schemo for the trem.
The speed pot is wired backwards on the layout, I will fix that on the amp and drawing.
Brad :icon_biggrin:
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take a look at reply #10 of the u-tube link to Delbert McClinton at the CMAs with his gitar man (white Strat) playing through an old 5G9.
#10? I got 'Too Much Stuff'. Danged if I could see any tweed amps in there. Gotta link?
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Insert a footswitch, or connect an alligator jumper from the hot lug to the ground lug.
That will kill the trem on this amp.
Ah, yes. I see that now.
Different test: unsolder the 22k from the center lug of the balance control. Trem now?
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take a look at reply #10 of the u-tube link to Delbert McClinton at the CMAs with his gitar man (white Strat) playing through an old 5G9.
#10? I got 'Too Much Stuff'. Danged if I could see any tweed amps in there. Gotta link?
No, it should be Somebody to love.
30 seconds in, on the right.
Just looked at it again and it looks to me that the other 2 guitar players got tweeds (maybe copys) and the white strat player is playing a custom amp?
Does it sound like a tweed bias-vary trem to you? Doesn't sound like a BF to me?
Brad :icon_biggrin:
Delbert McClinton - Somebody to Love (http://www.youtube.com/watch?v=5TlaDUHMcfA#)
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Here's the trem tube voltages.
Sluckey pointed out they should not be steady, so the osc is not working.
Here's the trem tubes dcv;
Driver/CF
Plate, pin 1+ 410vdc
Grid, pin 2= 270.4vdc
Cathode, pin 3= 272.4vdc
OSC
Plate, pin 6 =270.4vdc
Cathode, pin 8= 2.06vdc
When I turn up the Depth control pot the amp gets louder, wither the trem FTS is on or off.
Thanks, Brad
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Gonna put a 100K back on the socket? Will you need to replace the socket too?
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Yes and yes. I'll get to it tomorrow.
Brad :icon_biggrin:
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I still don't know why the trem osc is not wobbling. Near as I can tell, the OSC circuit is wired IAW the schematic. I'll look some more tonight. I think a working ohm meter will be very valuable troubleshooting this.
OTOH...
When I turn up the Depth control pot the amp gets louder, wither the trem FTS is on or off.
That's because the depth control is wired wrong. As is, it's part of the voltage divider network for your bias bal/adj circuit. Changing the depth control changes the bias! That's a bad thing.
I'll attach a drawing later. I'm too frustrated with Doug's nonresponsive server right now.
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I still don't know why the trem osc is not wobbling. Near as I can tell, the OSC circuit is wired IAW the schematic.
I've been over it 12 ways to sunday and I think it's wired up right too. I'm leaning towards a bad socket at this point, will see.
What if the 25uF/25v on pin 8 of the osc. K is bad? Could that be the problem?
The depth pot seems to be OK cause it's changing the bias when rotated.
That's because the depth control is wired wrong. As is, it's part of the voltage divider network for your bias bal/adj circuit. Changing the depth control changes the bias! That's a bad thing.
Should be fine when I get it working and wire the pot right?
When I rotated the depth pot 180deg. in the layout drawing I didn't flip the 0/X of the pot. This is another reason just to rewire the whole thing.
When I drew up the layout I thought it might be good to use eyelets on the board and point to point layout and to keep the FTS right next to the tube socket, as to keep all of the circuit together in 1 place, so no osc. leakage problems to anything else, ie, ticking. But it's a pain to see it and to re-work it, so maybe not such a good idea after all?
I think a working ohm meter will be very valuable troubleshooting this.
I'll go over to RS today and get a new meter.
Thanks for the help, Brad :icon_biggrin:
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The depth pot seems to be OK cause it's changing the bias when rotated.
That's because the depth control is wired wrong. As is, it's part of the voltage divider network for your bias bal/adj circuit. Changing the depth control changes the bias! That's a bad thing.
Should be fine when I get it working and wire the pot right?
What I was following was that the Speed control was wired backwards, rather than the Depth. Either way, ordinarily, the Depth control setting would not alter the bias. However, I believe the Bias Balance and Range controls provide the alternate path to ground that usually wouldn't exist in that part of this circuit.
What I propose is to unhook the 22k resistor from the Balance control, just to eliminate a variable.
You are right though, that you have what appear to be good voltages and therefore a functioning tube stage in your oscillator, but it's not oscillating. The path around from plate output to grid input most then not be correct, or that 25uF cap is shot; otherwise, the oscillator would oscillate.
Be sure to know that the feedback path is not just the caps, but also the resistors to ground. If any of those don't have a solid ground, they are effectively not in the circuit. If you have only 2 RC stages (series cap, resistor to ground), you will get close to but not all the way to 180 degrees (except maybe at an extreme frequency). The oscillator will ring, but not oscillate.
Be 110% sure of all your oscillators caps and resistors/grounding.
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Thanks HBP,
I was wondering if I had the speed pot wired backwards (O/X) also. I'll fix that too.
I would have lifted 1 end of the 22K as you said but I had snipped out the 100K from across the tube socket. I think I'll tack in a 100K and then lift that 22K or re-wire the speed pot 1'st just to help track down what exactly is wrong. Wont take long.
I bought a new meter at RS.
I need to do some things around the house 1'st then I'll start in on the amp again.
Thanks guys, Brad :icon_biggrin:
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The depth pot seems to be OK cause it's changing the bias when rotated.
NO! THE DEPTH POT SHOULD NOT CHANGE THE BIAS VOLTAGE.
Try this... Monitor the bias voltage on pin 5 of either output tube. (You may want to remove the power tubes for this, or kill the B+.) Now rotate the Depth pot from one end to the other. What is your bias voltage at each extreme of rotation?
The dc bias voltage should be rock solid when rotating the Depth pot. You could even damage your output tubes if the bias voltage goes too low.
Compare the two circuits below. You'll see what I'm talking about. The bias voltage must feed the depth pot from one end only, not be fed into the pot from one end and out on the wiper. Doing it your way just puts another variable resistor in the bias voltage divider string.
===========================
Now, this has nothing to do with the trem osc not working. That's another issue. We can't go any further with troubleshooting the oscillator until you put that 100K back on the socket (and replace the socket if pin 7 is compromised).
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NO! THE DEPTH POT SHOULD NOT CHANGE THE BIAS VOLTAGE.
I'm sorry, it went right over my head earlier when you told me about this.
I checked the bias as you said and yes rotating the depth pot changes the bias. The 6V6's are set for 20mA's each with -41vdc bias.
Rotate the depth pot and it goes from -41vdc to -11vdc.
Next I'll lift that 22K R as per HBP.
I see/understand you drawings, thank you. I'll lose the balance control. Even though both have the 250K depth pot in series with the bias, with the balance/range control pot in place as I have them, it gives the bias a path to ground _after_ the 250K and that's the hitch.
I didn't burn anything up, all is fine, PT, OT 6V6's. The 6V6's never even red-plated. :laugh:
RS meter was dead/broken from the get go, took it back. Where you plug in the test leads was shorting and all it did when trying to take R/C/Diode measurement's was buzz for continuity. :cussing: It also was a pain to get at the 2 fuses. You have to take out _8_ screws and then pull out a PCB from molex type sockets just to get at them. :BangHead: :cussing:
Went to HD and bought a Klein, seems to be solid at the test lead jacks, I think I'm gonna like it.
I spent yesterday with my wife food shopping and we cooked up a couple of gallons+ of spaghetti sauce, ground beef and Italian sausages, well freeze at least half of it. We had a great time and dinner was delicious. :icon_biggrin:
Now that I have a working meter again, I'll move forward with fixing the term. osc.
Also, sometimes I need time to think things thru. But once it gells in my mind, then I can move forward again.
Thanks for all the help, Brad :icon_biggrin:
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I want to see how your bias works out. I've got a bet it is better than dual bias. I am going the dual bias method, but I did get the mini 25kl pots so if yours is best I can copy.
Hi Ed,
Well it's not going to work in this amp. :sad:
But, I did find it _very_ easy to use and it was _no_ problem to adjust the 2 tubes @35mA each to within 0.2mA and that was with only 1 meter. Not to shabby. :icon_biggrin:
Now they were a matched set and I didn't mess with it very much, but I'm a beliver at this point.
I'll try it again in the next build with grid bias for sure.
Brad :icon_biggrin:
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Bias wiggle trem is less effective if there is too much tube current in the 6V6s, because trem wiggle ends up 'fighting' the output tube current.
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OK thanks, I remember you and others posting that before to help guys get their trems working.
When try to post the link to Delbert it goes to the pic. screen for the clip.
Just look up Delbert McClinton, Somebody to Love, on you tube.
Brad :icon_biggrin:
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When I first saw your bias/balance/trem circuit on Ed Chambley's Princeton thread, I thought it was simple but elegant. But then when you said changing the depth changes the volume, I decided to look more closely. And there it was! It finally hit me! And now that you say the bias drops to -11vdc, I know you have to change that part of the circuit or risk burning up your output tubes.
If you insist on splitting the two 220KΩ grid resistors to be able to balance bias, then I don't see any way around using a dual pot for depth control of the trem. Tell me, do you REALLY want to be able to balance tube bias to the gnat's ass, or do you just want that swamp trem sound on that video? You decide, but either way, you gotta change that bias part of the circuit.
I started drawing out a schematic using your circuit but with a dual depth pot. It's 80% done, but I decided to hold off until I see where you're headed with this issue. I vote KISS, single bias adjust and single depth control. Heck, the original didn't even have adjustable bias and it was a good amp.
Now, back to the trem circuit... The fact that the oscillator is not working is totally unrelated to the bias circuit problem(unless you hosed the wiring somehow, and I don't think that's so). Let us know when you have the socket changed out and the 100K plate resistor installed on the socket.
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I see/understand you drawings, thank you. I'll lose the balance control.
I didn't burn anything up, all is fine, PT, OT 6V6's. The 6V6's never even red-plated. :laugh:
Now that I have a working meter again, I'll move forward with fixing the term. osc.
Also, sometimes I need time to think things thru. But once it gells in my mind, then I can move forward again.
I know the post was long so I boiled it down to the above.
I think your right, I'll lose the balance and just go with a bias adjust control, that'll be just fine. :icon_biggrin:
And yes swamp trem it is. That is, too me, the most important part of this amps sound.
And yes I don't need to balance the PP pair of tubes down to a gnats butt. :laugh: But it is nice to know it will work fine on a PP grid bias amp without bias vary trem.
With that being said, I thought about how to get around the depth control and I thought it might be to use a dual pot. I figure you need 2 paths for the PP bias. For future reference it would be interesting to see your idea later.
When I first saw your bias/balance/trem circuit on Ed Chambley's Princeton thread, I thought it was simple but elegant.
I wish I could say it was my idea, but it's not. (and I said that then) It's from Kevin O'Connor's TUT books.
Edit; But it was not on/for a vary bias trem. amp, I tried to add it in and now I see it will not work in that amp.
Thanks, Brad :icon_biggrin:
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OK, I'll finish the drawing. I might name it Rube or something appropriate. :grin: It will be very similar to Ed's cut/paste drawing, but refined in Visio. I'll keep following to see when we can resume troubleshooting the trem osc issue.
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Yes, I've heard of a MR. Goldberg. :laugh:
And thanks again Sluckey.
Brad :icon_biggrin:
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Well guys, I just finished cutting the chassis to fit a dual pec pot. They will not fit in the angle front. BWT, I am replying on a brand new I7 processed 17 inch dell laptop. I do not foresee any problems. The PE pot is acurate as hell and the 2 mini 25kl bias pots are as well as they are PEC as well. I have gone a little crazy with mods, so the build is slow. I wired the heaters and am waiting on a couple of caps. I have finished the schematic and cannot see any reason why it will not work.
Yes Leo did do it without all these additions, but he never built a blackface with bias vary tremolo with a mid and and adjustable NFB along with a Dual Rectifier with a Deluxe OT with 4-8-16 ohms and used 7c5 power tubes with loctal sockets.
Like I said, I am having a ball with this build and I assure you when I am done and i am playing through this things with a tweed with 2 10's and 2 single 12's, 1 4 ohm and the other 16 ohms with blond tolex, it will be unique.
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The PE pot is acurate as hell and the 2 mini 25kl bias pots are as well as they are PEC as well.
I got my mini 25KL locking pots from Weber. Please tell me/us more about your mini pots.
Brad :icon_biggrin:
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Please tell me/us more about your mini pots.
called RV6 pots - miliary designation for the form-factor. RV4 are the 24mm pots you're used to seeing that are made by PEC.
291 in stock...
http://www.digikey.com/scripts/dksearch/dksus.dll?lang=en&mpart=RV6LAYSA253A&vendor=98&cur=USD (http://www.digikey.com/scripts/dksearch/dksus.dll?lang=en&mpart=RV6LAYSA253A&vendor=98&cur=USD)
--DL
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Thanks DL.
Brad :icon_biggrin:
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The PE pot is acurate as hell and the 2 mini 25kl bias pots are as well as they are PEC as well.
I got my mini 25KL locking pots from Weber. Please tell me/us more about your mini pots.
Brad :icon_biggrin:
Brad, man I am soooooooooooo sick of the inferior crap from overseas. In most places Alpha pots work, but they are NEVER close to accurate. Check out one of their audio tapers to a cts and you will see what I mean.
1 2 KKA2541S28-ND POT 250K OHM 2W DUAL LOG TAPER 0 34.37000 $68.74
2 2 RV6L253C-ND POT 25K OHM CARBON 1/2W 0 10.04000 $20.08
Here are the part numbers at Digikey. PEC are made in Canada. I had about 40 Alpha pots. Yesterday I traded all my Alpha pots to a friend for come cabling. I am done with them. Bourns will be used in non-critical areas like if I am doing something like an adjustable NFB. CTS linear are pretty good. I had a 1meg Alpha pot in the volume position of a custom amp I have been building and having trouble with. New pot. Put a MM on it and it measured 420k full turn. I thought there was something wrong with my meter. Checked it with another and got the same thing.
Maybe I am just snakebit where Alphas are concerned. A lot of the guys here use them and make wonderful amps. I checked the reverb pot on a deluxe I built a couple of years ago. It is supposed to be 100K. Been having trouble with the reverb. It measured at 1/4 turn 110K then dropped a little the I passed half a turn and it went flying by 100K and ended up at at 180K.
As Weber in concerned. I love their speakers. They stock very few good parts, but do sell Mercury and Heybour.
I do check them before installing them and know it in advance of using them so it is stupid on my part, but it you order a list of materials sometimes it is the only one you have. I have many 1 meg pots, quite a few 250, but I usually dont stock up on 100K as there are not many uses for them.
I did not check any more. I checked all my amps and ordered the CTS Doug had. I called Steve at www.apexjr.com (http://www.apexjr.com) as he has very nice NOS pots and Bournes and got what he had that would work and ordered the rest from Digikey.
Sure they are expensive from Digikey, but we put a lot of hours in these builds. If I have to build one less amp because I am using a quality pot, so be it.
As you can probably tell, I am a little more than irritated with the Taiwanese bullcrap.
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The _Swamp Tremolo_ is Now Working! :happy1: Wa Wa Wa Wa Wa ....... :l2:
And it sounds _very_ good to me. Waaaay better than my old BF SR and BF PR trem's, no doubt at all. :blob8: And I haven't even run it with the stand alone reverb yet!
Good news is it's working fine, so far. Bad news is I don't know exactly why? :cussing:
The osc. was wired right, but the speed pot was wired backwards and the bias/balance was a problem.
I wonder now if HBP was right about the bias/balance having a 2'nd path to ground and bleeding off the term. signal, just like it was messing with the bias? I never lifted the 1 end of the 22K R as HBP suggested because I would have had to tack a 100K R back in across the socket and I just wanted to get it fixed.
So... I took out the term. socket and everything that was wired to it and put in a new one. Put in all new R's/C's that were wired to the socket, pots and my 1 solder eyelet lug I had made, which is the true point to point section of my layout for the term. I made sure I measured all the new R's/C's (just as I did last time too) and also once again measured all the other R's/C's on the eyelet board, all were right. I changed the cathode by-pass 25uF@25v for the osc, even though the 1'st one measured fine, figured why not? Re-wired the bias to a single bias adjust and re-wired the backwards speed pot so it's now correct. I also had to re-do 2 sections of the twisted pair heater wires for the term. tube, that ran from the pilot light to the term tube, then to the PI tube because the heater wires insulation was a mess after taking out the term. tubes socket.
All in all it took me a long time, 8 hours? This point to point wiring with it's lead dress is IMO, _much_ harder than using an eyelet board and running the wires back to the socket, much, much easier, IMO. Also, I had to keep looking back at the schemos with ever step to make sure it was wired right. :laugh: I do think the lead dress is better this time and looks better too.
I still need to play with the bias R's a little to limit the high and low ends of the bias swing.
And I do need to slow down the term. a little more. Right now the osc. has 2 @ 0.02 and 1 @ 0.01 for the caps. So I need to increase the cap values a little? It's got way more than enough depth. The term. on/off FTS works fine, no pops.
I'll post pics in the next day or two.
Thanks to _ALL_ of you for your technical and moral support!!!!! As always, You guys are the best!!!!!
Brad :icon_biggrin:
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I do need to slow down the term. a little more. Right now the osc. has 2 @ 0.02 and 1 @ 0.01 for the caps. So I need to increase the cap values a little?
Glad you got it sorted. Yep try tacking .01uF in parallel with that first .02uF off the LFO plate
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Glad you got it sorted.
Thanks, me too. :laugh:
Pete you were right, these bias-very trems are killer, whaaayy more soul than roach style trems!
Yep try tacking .01uF in parallel with that first .02uF off the LFO plate
Ok, thanks, that's what I thought.
Brad :icon_biggrin:
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Congratulations! I has a feeling the trem would heal itself during the socket replacement. :wink:
Here's that dual bias circuit I was working on. I bet you like the amp just as it is though. Sometimes too many bells and whistles are just that! :icon_biggrin:
Play on...
Oh, and here are a couple pics of the only dual bias I've done. Pots are the RV6 type. Amp is Sunn Sceptre.
http://home.comcast.net/~seluckey/amps/sunn/mod_1.jpg (http://home.comcast.net/~seluckey/amps/sunn/mod_1.jpg)
http://home.comcast.net/~seluckey/amps/sunn/mod_2.jpg (http://home.comcast.net/~seluckey/amps/sunn/mod_2.jpg)
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Hey, you got it going! What a lot of work! Well, all I can say is persistence paid off and now you get the reward. They are such neat amps and yours looks like a killer; I'd be proud to have one as nicely built as yours. Will you post a sound clip or two?
Congrats!
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Congrats!
I don't know that my suggestion to simplify the bias while troubleshooting was the root of the problem. That was just to remove extraneous issues while you were sorting the oscillator.
I'm betting something wasn't quite right with the Speed pot, feedback components, the socket or the oscillator's 100k load on the socket. All the things you did to revamp that area managed to catch the one item that was holding up the show.
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Thanks for sharing that schematic Steve.
FWIW I've found (with 5G9s) the trem slam becomes even more intense if that 1M resistor (that's in the voltage divider after the CF) is decreased to about 470k. This saves you having to cool the 6V6 bias down 'too much'. You may have to tinker with final values (or adjust the bias) in order to prevent 'helicoptering' and depending on taste. (@ brad - not saying that everyone should automatically do this - its just more of a tweek-thing if you're bored, after the circuit has been built and is working)
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Great, I am glad you got it
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Congratulations! I has a feeling the trem would heal itself during the socket replacement. :wink:
Here's that dual bias circuit I was working on. I bet you like the amp just as it is though. Sometimes too many bells and whistles are just that! :icon_biggrin:
Play on...
Oh, and here are a couple pics of the only dual bias I've done. Pots are the RV6 type. Amp is Sunn Sceptre.
http://home.comcast.net/~seluckey/amps/sunn/mod_1.jpg (http://home.comcast.net/~seluckey/amps/sunn/mod_1.jpg)
http://home.comcast.net/~seluckey/amps/sunn/mod_2.jpg (http://home.comcast.net/~seluckey/amps/sunn/mod_2.jpg)
Thanks for the Schematic. It looks familiar. I have a couple of questions. What is LFO? Why do they call the control Depth and not Intensity? On the schematic, you have 2 caps without values and resistors as well. Is that because they will vary according to the bias tap voltage and also the application of the circuit?
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Here's that dual bias circuit I was working on.
I wonder if his circuit as-is could have a bias balance that replaces the 220k bias feed resistors?
Say, the Depth pot wiper feeds the wiper of a 500k linear pot, whose outer lugs then go on to the output tube grids. Or a 250kl pot, with 120k build-out resistors on either end.
What is LFO?
Low-Frequency Oscillator
Why do they call the control Depth and not Intensity?
Gibson and Gretsch amps often call that function "Intensity". Fender just said it different. And there are some amps out there that say "Frequency" instead of "Speed".
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congrats! glad you got it working.
--DL
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you have 2 caps without values and resistors as well. Is that because they will vary according to the bias tap voltage
Actually there are 3 caps. 10-50uF should be fine. I didn't show resistor values because you need to juggle depending on the AC voltage input. Willabe's values should be just about right for his circuit.
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Could you post a sound sample of the now working tremolo, please?
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Thanks guys.
I has a feeling the term would heal itself during the socket replacement. :wink:
I wasn't so sure, I kept looking to see if I had wired somthing wrong, but other than the speed pot being backwards it was correct. All the parts values were correct too. :dontknow:
Thanks for your dual bias idea and drawing. Looks good to me. I saved it. I'm going to leave the bias it like it is.
FWIW I've found (with 5G9s) the trem slam becomes even more intense if that 1M resistor (that's in the voltage divider after the CF) is decreased to about 470k. This saves you having to cool the 6V6 bias down 'too much'.
I'll keep that in mind. So far it's got plenty of depth as is.
Could you post a sound sample of the now working tremolo, please?
I'm sorry T but I don't have any recording gear any more. I haven't realy put it through much playing yet, but I will say it seems to be a little cleaner than my 5E3 and to me, the trem sounds rounder, warmer, smoother and deeper that a BF roach trem.
Brad :icon_biggrin:
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Thanks guys.
I has a feeling the term would heal itself during the socket replacement. :wink:
I wasn't so sure, I kept looking to see if I had wired somthing wrong, but other than the speed pot being backwards it was correct. All the parts values were correct too. :dontknow:
Thanks for your dual bias idea and drawing. Looks good to me. I saved it. I'm going to leave the bias it like it is.
FWIW I've found (with 5G9s) the trem slam becomes even more intense if that 1M resistor (that's in the voltage divider after the CF) is decreased to about 470k. This saves you having to cool the 6V6 bias down 'too much'.
I'll keep that in mind. So far it's got plenty of depth as is.
Could you post a sound sample of the now working tremolo, please?
I'm sorry T but I don't have any recording gear any more. I haven't realy put it through much playing yet, but I will say it seems to be a little cleaner than my 5E3 and to me, the trem sounds rounder, warmer, smoother and deeper that a BF roach trem.
Brad :icon_biggrin:
Just plug a microphone in your computer and use windows medial player and record. It won't be like pro tools, but we will get to hear the amp.
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Yeah, without sound clips it doesn't exist. :laugh:
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Ok, I'll look around for a mic, my 2 good mics (that I still have) are at a friends. I need to change my strings too.
I might as well learn how. :think1:
I've only had a computer for about 3 years so I know very little about different things they can do and how to make them do it. :laugh:
Brad :icon_biggrin:
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Don't feel bad it took me years to figure out my computer could do other stuff besides looking up nude pics of women. :laugh:
Glad to hear you got it going.Can't wait for the clips.
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Thanks buddy. :icon_biggrin:
I'm not doin to bad with it, but learning more is always good.
Brad :think1:
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Alrite Wilabe
So ya finally arrived!! Except a few tweaks :icon_biggrin:
Ye haw!! Boy the drama was getting intense---now I can relax
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Ye haw!! Boy the drama was getting intense---now I can relax
:laugh:
Thanks Plate. She go wiggle now. Wa Wa Wa Wa Wa Wa Wa......
Brad :l2:
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I found an old RS condenser mic and put in a new battery. But when I record with it on playback all I get is a _very_ low volume even with the speakers turned all the way up, all 3, the speakers and on the Real-Tech and on the computers screen.
I'm going to put this in Audio/Video.
Thanks, Brad :think1:
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Ok, I got it to record, but I don't know how to post it.
I posted for help in sound-bits and in video/audio.
Thanks, Brad :think1:
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Ok, I got it to record, but I don't know how to post it.
I posted for help in sound-bits and in video/audio.
Thanks, Brad :think1:
When you get it posted, post a link. I can't find my way around here very well. I can't wait to hear it as I am sure is Kewl.
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Here's a sound clip of the trem.
Mid 80's (?) 62 reissue Strat, rosewood fret board, stock pups, middle pup on, Tubby Tone 12" speaker in a mojo single 12" open back cab and stand alone reverb in the front. The very end is without the trem, 6V6' are set to only 20mA each at this time. I'll set them higher later.
I don't play very much any more but you can still get the idea.
Brad :icon_biggrin:
http://soundcloud.com/brad-willabe/5g9-trem-sounds (http://soundcloud.com/brad-willabe/5g9-trem-sounds)
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So trippy that it just keeps on makin' you wanna play huh?
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That is beautiful. Why the disclaimer I don't play much anymore. Playing was very clean and articulate. Heat those tubes up a little and get that bastard screaming. It sounds like it would have a great tone for the E box at fret 12. Doesn't sound like it would get shrill at all. I'll bet you could get a great woman tone with some Humbuckers.
Building takes time away from playing, that is for sure. I made a deal with myself a long time ago that I play time equal to building time. I have been active playing since the mid 70's and have lots of friends who do gigs. I am not "In a band" per say, but there are a few local great vocalists who call me for their guitar man. A long time ago I met Rick Derringer and asked him how did he ever get the opportunity to play with so many different people and continue working. He said there are 3 simple rules. Be on time, know the material and always remember you are no more than part of the foundation for the singer.
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That tremolo sounds fine, fine, fine. It was a lot of work but you got it going in the end; excellent. I would have liked to hear it at the extremes of the speed pot, though.
I was interested in hearing that because two days ago I did a review of the new Fender Excelsior amp for another forum and I played around with its tremolo. I did a clip to show what the Excelsior sounds like for me and I began with the trem: https://www.box.com/s/139c7f6cfca04807565e (https://www.box.com/s/139c7f6cfca04807565e) (only the first section of the clip uses the trem)
I'm not trying to hijack the thread here - my point is that while the Excelsior has an easy-to-use tremolo (it doesn't use a tube for the trem, BTW), it isn't one of the better ones I've heard, and the effect gets too weak as you slow its rate down. Yours sounds like what I want to hear from an amp with trem. Anybody curious about the Excelsior can read my comments about it here: http://agileguitarforum.com/showthread.php?tid=21911 (http://agileguitarforum.com/showthread.php?tid=21911)
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Re the excelsior vs the 5G9 trem, the trem circuits in both amps are fairly different (and the excelsior uses a source follower to buffer the signal) Brad's amp has the classic hypnotic trippy slam that only the 5G9 trem has)
(http://farm9.staticflickr.com/8153/7481643948_34ab696096_b.jpg)
(http://farm8.staticflickr.com/7227/7330408312_1d3eed909f_b.jpg)
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So trippy that it just keeps on makin' you wanna play huh?
Now that you mention it, it does sound a little late 60's-ish, especially when I drop the whammy bar. :laugh:
I was a little worried I'd have a hard time with not staying in sink with the term speed but so far no problem. :dontknow:
I _really_ like the sound of it, gives a nice texture on certain things/songs. I could have used it in the blues clubs on a hand full of tunes back then, I think the guys/players would have loved it too.
And yes it does make me wanna keep on playing. :laugh:
That is beautiful. Why the disclaimer I don't play much anymore. Playing was very clean and articulate.
Thanks Ed for the kind words.
Thing is I used to play _a lot_ when I was younger. 3 - 4 hours a day at home was pretty normal and 6 to 8 was fairly common + a gig or 2 a week and I sat in every chance I got (4, 5 times a week) with who ever was playing in the blues clubs that I hung out at the time. Then I left the clubs/bars and played a lot in church. I would also go on song writting jags at times, logged a lot of time on those too. Also had a Tascam 8 track real to real 1/4" tape/mixer that I spent some time with. It kinda all went in cycles through the years of lots of playing time and not so much at other times. I'm on my 4 set of frets on my Strat. :dontknow:
I pretty much had stopped all together when my parents passed away and my brother came to live with me. He was blind and his health was bad, seizures, plus a long list of other compounding health issues. He passed on now about 2 1/2 years ago. My closest aunt & uncle also passed during the same 5 (?) year period. Any way it was just too much for me, maybe now I'll get back to playing a little more.
A long time ago I met Rick Derringer and asked him how did he ever get the opportunity to play with so many different people and continue working. He said there are 3 simple rules. Be on time, know the material and always remember you are no more than part of the foundation for the singer.
I love Derringers playing. "I Think I'm Gonna, Jump, Jump, Jump" is unbelievable.
I think what he told you is very true and wise and the older I get to me the _song_ is the boss. I try to play what fits the song and it's singer. The _song_ is everything.
I would have liked to hear it at the extremes of the speed pot, though.
Well, you did hear 1 extreme, the slow end. :laugh:
I have to add a little more capacitance in the LFO to slow it down a little more. Full up speed is so fast you can't really even tell it's on.
I'm working on the cab for it now. I glued the 4 sides up today about 2 hours ago. I'll post in cabs and speakers about with pics as I go.
Thanks, Brad :icon_biggrin:
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I wasn't implying that the Excelsior uses the same circuit; only that it doesn't sound as good.
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So trippy that it just keeps on makin' you wanna play huh?
Now that you mention it, it does sound a little late 60's-ish, especially when I drop the whammy bar. :laugh:
I was a little worried I'd have a hard time with not staying in sink with the term speed but so far no problem. :dontknow:
I _really_ like the sound of it, gives a nice texture on certain things/songs. I could have used it in the blues clubs on a hand full of tunes back then, I think the guys/players would have loved it too.
And yes it does make me wanna keep on playing. :laugh:
That is beautiful. Why the disclaimer I don't play much anymore. Playing was very clean and articulate.
Thanks Ed for the kind words.
Thing is I used to play _a lot_ when I was younger. 3 - 4 hours a day at home was pretty normal and 6 to 8 was fairly common + a gig or 2 a week and I sat in every chance I got (4, 5 times a week) with who ever was playing in the blues clubs that I hung out at the time. Then I left the clubs/bars and played a lot in church. I would also go on song writting jags at times, logged a lot of time on those too. Also had a Tascam 8 track real to real 1/4" tape/mixer that I spent some time with. It kinda all went in cycles through the years of lots of playing time and not so much at other times. I'm on my 4 set of frets on my Strat. :dontknow:
I pretty much had stopped all together when my parents passed away and my brother came to live with me. He was blind and his health was bad, seizures, plus a long list of other compounding health issues. He passed on now about 2 1/2 years ago. My closest aunt & uncle also passed during the same 5 (?) year period. Any way it was just too much for me, maybe now I'll get back to playing a little more.
A long time ago I met Rick Derringer and asked him how did he ever get the opportunity to play with so many different people and continue working. He said there are 3 simple rules. Be on time, know the material and always remember you are no more than part of the foundation for the singer.
I love Derringers playing. "I Think I'm Gonna, Jump, Jump, Jump" is unbelievable.
I think what he told you is very true and wise and the older I get to me the _song_ is the boss. I try to play what fits the song and it's singer. The _song_ is everything.
I would have liked to hear it at the extremes of the speed pot, though.
Well, you did hear 1 extreme, the slow end. :laugh:
I have to add a little more capacitance in the LFO to slow it down a little more. Full up speed is so fast you can't really even tell it's on.
I'm working on the cab for it now. I glued the 4 sides up today about 2 hours ago. I'll post in cabs and speakers about with pics as I go.
Thanks, Brad :icon_biggrin:
In life there is always a storm coming. You have seem to stay in the trenches with integrity. That's being a real man. I too have had to lay aside playing from time to time, but if it's its in your blood it always will be.
I absolutely despise recording, so I bought Pro Tools. Now if anyone wants me to record, I tell them to send me the files and I will send the guitar parts back. I don't even like playing clubs, but I still do sometimes. I like fairs and car shows, but my favorite is I have a soundproof basement. My buddies come over. We fire up the grill and turn on the amps and PA.
I spent about 2 years learning country style and there are so many wannabe country singers that I get more work than I want. They always want to record. I only play. Nothing like the gel that happens when you are playing with others who are good players.
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Ed again, very kind words, thank you.
I like me some country. Vince Gill and Lee Roy Parnel are 2 of my favorites, I also love Patty Loveless. :icon_biggrin:
I got around to setting the bias up from 20mA per tube to 35mA per tube. I have a NOS 12AY7 in the 1'st position and with the amp full up with the trems depth full up no red plating on the 6V6's. Trem still sounds great and still has plenty of depth, more than I need or would use.
I played the amp for, mmm, almost 3 hours last night, with the volume set to 11:00 to 12:00, tone set around 1:00 to 3:00 plugged into the #1 bright input jack. Ran my late 80's (?) reissue 62' rosewood fret board Strat with stock SC pup's (I need to get a set of Fralins in it!) and my early 90's (?, first year they were made) Heritage Les Paul with HB's (tuned to open E for slide), into the 6G15 verb I built. Tone - Tubby 12" hemp cone, alnico speaker in an open back Mojo 1-12 cab. I need to try a 12AX7 in the first position.
I gotta say, this amp sounds real good to me. I'm very glad that I made it. Very nice sustain without a ton of distortion. Slide notes hang on and sing nicely, as well as finger played notes. Very quite too. I bet my old (late 40's - early 50's) Gibson lap steel is gonna sound great through this set up too, but I need to have the pup re-wound as it gave up the ghost. I'm very happy with the overall sound and have no complaints so far. I could see gigging with this set up no problem, well depending on the size of the room.
Brought it to a friends church sunday and had a jazz guy play his 80's Ibanez Artist (335) through it. He liked it a lot, said it was very "round" sounding. (He's got a DR re-issue that he plays through at church.)
Brad :icon_biggrin:
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Nice work Brad, I'm sure that my wife would rather me do some more practice and less building for her ears sake!!!! :icon_biggrin:
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Thanks Timbo.
Yeah, I'm luckey like you, my wife likes it when I play.
Brad :icon_biggrin: