Tone Bender MKII

[Matt]

I've been on a bit of a fuzz kick lately. Basically, i made an ill advised eBay purchase of 100 gt308 Russian ge's. So I decided to put a few to use.

i learned a lot on this build. First of all, as many of you probably already knew, Tonebenders like Q1 to have some leakage. Couldn't get it to make a sound at first with the gt308. I found a thread where mac from DIYstompboxes recommended using a resistor from collector to base to simulate leakage. Bam! It was alive. A lot of different tones can be had by playing with the value of this resistor. In the end, I settled on a 1M5.

I spent the last three weeks with this thing on the breadboard trying different collector resistances. I would make an adjustment then come back a a day later to listen again.  I have to say that the effort payed off. This is the best sounding fuzz I've ever built. I
also ended up using bias pot for Q2. I found a thread where Jon had mentioned that this method is better than the more common bias pot on Q3.

Anyway, enough rambling, here it is. I've included a schematic for anyone who is interested. By the way, the HFEs that I used are 71, 74 and 79

[jalmonsalmon]

 Nice one!
I love tonebender mk II's
I have a few of thos gt308's as well and I may have to try some of those on the ol breadboard!

[cooder]

Nice classic one there, great build!

[Matt]

Nice one!
I love tonebender mk II's
I have a few of thos gt308's as well and I may have to try some of those on the ol breadboard!

Nice classic one there, great build!

Thanks! 
That's cool, let me know what you think. It'll be nice to have someone else's opinion.

[lincolnic]

Thanks for including your schematic for the Q2 bias pot -- I have a half-finished Tonebender build where I initially wired the bias pot for Q3, and I didn't totally love the result. I'll redo it for Q2 and hopefully be happy enough to box it up!