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Ok that was a seriously long pause... life interrupts (how rude)    I'm back to tweaking!

(edit, uh let me try that again) I measured across the LDR side and I'm getting nothing that low.  I get ~200K when not playing but it only goes down to 60K or so.  It still has the quiet static overlaid with a strong signal.

Thanks for your patience.

I replaced the diodes, I suspected one was broken, and it was, at least once I removed it... here are the measurements now:

1 - 5.0v
2 - 4.6v
3 - 2v
4 - 0
5 - 4.6v
6 - 4.6v
7 - 2.9v
8 - 9.3v

Pin 7 changed considerably so at least that part helped.

Thanks so much, I will have to test this out when I get a few minutes free.  That's fantastic info.

> Set the comp to max and your threshold pot to 0K.

I presume by this you mean the sensitivity pot - set it to 0k so that the resistance across R7 is back to stock values?

Voltages:

input: 9.45 (Boss PSU)

TL072:
1: 3.76
2: 5.23
3: 2.68
4: 0
5: 4.62
6: 4.62
7: 7.72
8: 9.23



note: R7 is replaced by a pot soldered on the other side of the board.  The pot doesn't seem to make a huge difference so far...



(the connections on the bottom are not bridged)... so hard to get these in focus!

Note: I pulled off a trace on the daughter board so I had to make that ugly little jumper... it's soldered on the other side and anyway, that board seems to work.



I have an active preamp in my bass, plus it seems when I hit the low notes hard I hear the crackle. 

Anything else that might help?

Hi folks,

I finally built my afterlife, and crammed it into a 1590a... that was quite a task.

It all seems to be mostly working, very subtly... except I am getting some kind of distortion when playing my bass through it.  It's a high-end staticky type of distortion, I'm not sure where to look to see what is causing it.  It is mostly evident with my bass, higher notes on the guitar don't seem to bring it out as much.

I used a VTL5C3 and replaced R7 with a 50K pot with a 33k resistor in series (I changed that to a 47k, so that when the pot is dialled down it is in stock configuration).

What could be causing the noise?  How can I trace this?  Thanks.

well r3 and r6 are within about 10% of the ones he recommended for your transistors, so as long as your resistors aren't too far off from their own ratings it's probably not a big deal.  I'd probably leave those in and only change them out if something doesn't sound right.

out of curiosity, what are the hfe's of the transistors he sent you?

Q1 is marked 102 (L=125) and Q2 is 178 (L=174).  Not 100% sure what that means, sounds like the gains are on the high side?

I'm tempted to put his values in, just because.  R6 is within 10% but R3 is a little farther out of that range.  I was kinda wondering if my logic was sound in matching them up, and I think so.

I just got my set of Germaniums, but for the Zygote instead of Mangler.  Does this sound right?

His References vs Zygote Schematic
-----------------------------------
R3 = R3
R4 = (R4 + Tweak) [220R + Tweak] or
       (R4 + R5) [220R + 1k (in parallel with tweak)]
R5 = (R6 + 25k bias pot) [220R + 25k bias pot]
R6 = R2

The values he gave me are rather close, and in anticipation of my germaniums arriving I went and soldered in the Zygote values.  I'm wondering if they're close enough.  Here are the differences:

R3 = 27k (vs. 33k)
R4 = 680R (this is tweakable I guess)
R5 = 12k (somewhere midway on the bias pot)
R6 = 91K (vs 100K)

Is it worth pulling the 33K and 100K for these values or will the pots make those differences negligible?

Thanks

I am willing to make you a Zygote board, no problem.

PM me.

You guys are great... I already had an offer, but if I decide I want another one (quite possible) I'll get in touch with you.  Thanks!

That was my question, are these the handmade ones that he can't keep up with or has he just stopped making these for another reason?

Here I was, holding off on getting a zygote board until after taxes... and now they're gone.  Are they going to come back?  Is this one of your handmade boards you were talking about before, or is this one of the "offline" ones you are just putting on hold?

I'm curious if this will isolate the ground?  i.e. could I daisy-chain a PNP fuzz using this with other negative-ground pedals?