Two Tone Fuzz transistor layout?

[joelorigo]

I'd love to see a gut shot of your two tone fuzz

Me too! I just ordered this PCB today.

 

[scotheath]

I wasn't able to source any GT402 transistors but did find 2 PT416 for Q1-2 and a 2N404 for Q3 all in the right hfe for this pedal but after populating board with resistors and caps I had it dawned on me I should of left R7 out so I could get voltage correct and collector of Q3. What kind of voltage should I be looking for for the Q3 collector? I've only ever done 2 tranny fuzz face type circuits before and know Q2 collector voltage is important in that circuit.

 

[joelorigo]

I wasn't able to source any GT402 transistors but did find 2 PT416 for Q1-2 and a 2N404 for Q3 all in the right hfe for this pedal but after populating board with resistors and caps I had it dawned on me I should of left R7 out so I could get voltage correct and collector of Q3. What kind of voltage should I be looking for for the Q3 collector? I've only ever done 2 tranny fuzz face type circuits before and know Q2 collector voltage is important in that circuit.

What is the right hfe for the pedal? I have a "3 Knob Tone Bender Set" I bought from Small Bear that are about 55, 78 & 95. Do they need to be higher?

 

[PedalBuilder]

What is the right hfe for the pedal? I have a "3 Knob Tone Bender Set" I bought from Small Bear that are about 55, 78 & 95. Do they need to be higher?

A “3 knob Tone Bender” refers to a Tone Bender Mk. III, which has lower gain, low leakage transistors in Q1 and Q2, and a very leaky high gain transistor in Q3. Despite the similar name, it’s a completely different circuit than the Tone Bender Mk. I.5 and Mk. II circuits that comprise the Two Tone Fuzz.

For this pedal, I'd focus less on hFE and more on leakage; I've built great sounding Mk. II's using transistors with gains as low as the 30s and as high as the 400s(!), but they need to be leaky in order for it to bias correctly. There are lots of threads on Tone Bender Mk. II transistor hFE/leakage/voltages, so I'd recommend searching the forum to see what worked well for others.

 

[joelorigo]

A “3 knob Tone Bender” refers to a Tone Bender Mk. III, which has lower gain, low leakage transistors in Q1 and Q2, and a very leaky high gain transistor in Q3. Despite the similar name, it’s a completely different circuit than the Tone Bender Mk. I.5 and Mk. II circuits that comprise the Two Tone Fuzz.

For this pedal, I'd focus less on hFE and more on leakage; I've built great sounding Mk. II's using transistors with gains as low as the 30s and as high as the 400s(!), but they need to be leaky in order for it to bias correctly. There are lots of threads on Tone Bender Mk. II transistor hFE/leakage/voltages, so I'd recommend searching the forum to see what worked well for others.

I see.

When you say bias correctly, since there is no trimmer on this PCB your talking about having the correct leakage range on the transistors to elicit the proper voltage?

Also, in post #9 of this thread @DeadAirMD reports a great sounding pedal using GT402's from SBP which on their page lists "Most of these are very low leakage, anything leaky or unstable has been sorted out." It also says that "Leakage is below 300uA." What is considered "leaky?"

GT402 PNP Germanium Transistor

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