- Feb 16, 2008
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- John K Custom Basses
yep. since I've rebuilt so many original 370's, I used the original NOS transistors as opposed to substitute/equivalents in the pedal version.
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Acoustic 370 Power Amp Sim Pedal
- Thread starter johnk_10
- Start date
I want one. I love the fuzztone my 320 and 370 get cranked up past noon but I pretty much never need them turned up loud enough to get there. That Acoustic power amp distortion in a pedal would be a godsend.
Freq'n' coolio!
(as per usual)
I would've liked to have seen this thing when it was still on the breadboard. Any pics of that?
Also... you've offered PCBs in the past – any chance of this design being offered?
Have you tried this with your 360+ pedal?
(as per usual)
I would've liked to have seen this thing when it was still on the breadboard. Any pics of that?
Also... you've offered PCBs in the past – any chance of this design being offered?
Have you tried this with your 360+ pedal?
- Feb 16, 2008
- 21,240
- 23,637
- Disclosures
- John K Custom Basses
it never was on a breadboard. I just used the factory acoustic schematic and made a PCB for it., so it's not an emulator but the real thing, just scaled down to pedal output level as opposed to speaker output level.
here's a pic of the main PCB:
no. i'm not going to be offering PCBs of it.
yep, and it sounds awesome. it also sounds awesome all by itself.
Last edited:
- Feb 16, 2008
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- John K Custom Basses
BTW, I found a small error on my first prototype and made a new corrected PCB (see post above) and it sounds a zillion times better now.
soundclip soon to follow.
soundclip soon to follow.
You continue to amaze and impress, sir. Straight to PCB without ever breadboarding it... Bravo!
Lookin' forward to the next soundclip!
Lookin' forward to the next soundclip!
- Feb 16, 2008
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- John K Custom Basses
quick soundclip of the 'corrected' 370 circuit:
Really nice! It sounds like that AGC limiter is keeping the output from going crazy square wave.
Good project John!
-Frank
- Feb 16, 2008
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- John K Custom Basses
thanks Frank. yes, since it's trim-able I can set how much AGC that I want dialed in. this thing has TONS of CLEAN output (so much that it can drive a poweramp!). IMO, it's the best clean boost that I've ever heard, and it can get pretty dirty too by cranking the input gain.
- Feb 16, 2008
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- John K Custom Basses
I haven't figured t out yet, but due to the complextity of the circuit and the cost of the NOS transistors, it wouldn't be cheap.
- Feb 16, 2008
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- John K Custom Basses
I cannot believe the stuff you're able to pull off. Are you going to make any to sell? I know they won't be cheap, but something tells me you won't have any problem selling them (me included).
I liked the dirtier voicing of the uncorrected PCB in the first clip.
If you could make a pedal that sounded like that, with new off the shelf transistors, you have 2 amazing new pedals.
- Feb 16, 2008
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- John K Custom Basses
i'm using a charge pump (LT1054). the DC jack takes in 9 volts, converts it to a bipolar 17.5V supply.
+17.5 for the main 370 amplifier board, and +17.5V & -17.5V for the TL072 on the input/AGC board, so the TL072 in effect is essentially running on 35 volts. and the relay bypass is running off of 9V at the DC jack.
here's a gut shot of it. there are 3 PCBs under the main board (the relay bypass PCB, the input amp/AGC board, and the bipolar converter board):
