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Most resistors used originally in these circuits had a 5% tolerance, which for a 29K would be roughly anywhere from 27.5K-30.5k. By that rationale, the 30K still falls within tolerance. You'll likely not hear a difference.

Search for mmbf5457 or mmbt5457 and mmbfj201 for the J201's. I seem to recal those being the part #'s

Any other early bets on it being another modified Supreaux Deux?

I've had a Tweaker 15 and 40 - fantastic little amps and extremely versatile - especially with decent tubes. And, like CJ said, you can pick them up pretty cheap.

Tangent: Anyone interested in a Pork Loin DIY project? I actually have a layout in the Etcher's Paradise folder. Not verified obviously.

Hell yeah!

Welcome, Pawel! Nice to have you here indeed.

http://www.madbeanpedals.com/forum/index.php?topic=16054

Yep, you've got it

The difference between the 500kA (logarithmic or audio taper) and 500kB (linear taper) is just in how the levels of gain are distributed across the sweep of the pot. The linear taper will get gainier quicker in the sweep (from 9:00 to 12:00 or so) while the log or audio taper will more gradually increase the gain - bunching more of it up past Noon on the dial. Log/Audio taper almost always works best for volume controls, but it's a personal preference for drive/gain controls - just depends on whether you like the gain spectrum bunched up more at the beginning or end of the dial.

I've noticed even Wampler has started using the SMD adapters in his more recent builds - seems to be the best way to get consistent, reliable JFETs any more. I seem to remember a few threads where members have tried to find reliable sources, but like Muadzin said they almost always turned out to be Chinese crap or barely meet specs.

Isn't the 1N5401 in the Darkside circuit used for reverse polarity protection? I wouldnt think a shottky diode would be ideal in that application - too much reverse current leakage.

Shane, your charge pump should have the "SCPA" designation, which means it switches at a frequency higher than audible range. The "CPA" chips switch at a lower freq which can be heard as a whine.

The Charge pump in the pedal is a TC1044SCPA From Mouser.  Is this the correct one? 

-Shane

Yeah sorry, wasn't fast enough with the edit - that should be fine. It's possible the chip got damaged though. I'd through a known good one in there temporarily just to eliminate it.

Shane, your charge pump should have the "SCPA" designation, which means it switches at a frequency higher than audible range. The "CPA" chips switch at a lower freq which can be heard as a whine.

EDIT: looking at your pics I see your charge pump is an SCPA. Maybe swap it with a known good one. If that doesn't help, check your power filtering.

I've used Langrex before - reliable parts, and he's usually willing to work with you if you're looking for particular hfe/leakage.

1971 Traynor YGM-3

Original mullard pre and power tubes (EL84) still going strong. I re-capped and installed adjustable bias, and threw in an Eminence Cannabis Rex. Fantastic vintage amp.

Great amps! I have a mid-70's Traynor YBA-4 that I picked up at a garage sale a while back - basically a 50W plexi/JTM circuit. It needs a recap and could use a better speaker, both of which I'll get around to eventually. It still sounds great as is!


Besides the Traynor, the only thing vintage in my collection is the player