Tone Bender MkII questions

[nbabmf]

I can't seem to get this guy quite dialed in.  Either it's nice and quiet, but extremely sputtery and gated... or it's crackly and noisy, but almost dialed in tonewise.  I'm using CV7355/2N1309 germanium PNP transistors, 25k trimpot on the collector of Q3 (sticking around 7 volts seems to be the best sound), and it's on a verified layout.  Q1-3 are around 70, 90, and 140 hFe, respectively.  I've tried a leaky one in Q1 and Q2, and in one position it's okay, but the other it's totally messed up.

What should I be getting for collector voltages on Q1 and Q2?  Q1 is right around 4.5-5, and Q2 is 0.15ish.  It seems to me like a transistor is "shutting off" with too much input signal because when I roll the volume down on the guitar, I can get it to stop gating out on me, but it's useless otherwise.  I'm wondering if maybe I need to replace one of the other resistors with a trimpot.  I'm just afraid of tweaking and tweaking, only to find out later that I passed by a perfectly good solution!

I've searched and searched.  I'm learning as I go, but apparently not enough.  It was so much easier building a Muff with these transistors... maybe because I have tons of them with hFe over 200, but only a few under.  Is it possible to adapt the circuit to higher gain transistors without losing the sound I'm going for?

[ibodog]

I recently built a Bender MKII and I used trimmers for the 2nd and 3rd transistors' collector resistors (AC125).  I liked ~-7V on both Q2 and Q3.  It was actually a little tough on the trimmers to get them dialed in to where they sounded good. 

[waltk]

On my first Tone Bender 3-knob build, I was getting the same symptoms you report - sputtery and gated or crackly and noisy.  It sounds like your debugging is already far beyond this, but my problem turned out to be having the wrong pinout on the transitors.  Once I turned them around, it instantly worked great. (FYI seems like my russian transistors have the emitter marked with a red dot instead of the collector).

[mac]

Q1 and Q2 should be low leakage, 50ua or less. Higher values will send both collectors down which is not good.
Q3 could be anything.

mac

[nbabmf]

The pinout was right.  The fuzz pot wasn't grounded. OOPS!

In the end, I had to swap out the transistors a bunch.  The one that sounded the BEST while I was playing was also the noisiest when I wasn't.  I put a trim pot in place of the 47k and tweaked that a bit, too.  We're good to go now!