Hi everyone. I ordered a Tone Vendor MK1 board a bit ago. I've made most of the fuzz box types in the past except for this one. I was happy to see that PedalPCB offered a board for the MK1. I've read most everything I could find on the internet about the MK1 and the data and opinions about the MK1 are all over the place. So, what is good data that works for building the MK1 and what is hogwash??? Lol!
Well, I built mine and here's a few observations that I've made... Hopefully this will help other builders:
I found that Q1 works best if it has a gain of around 55-70, it also needs to be "leaky", like around 200ua. This is because the leakage is what biases Q1. A higher leakage might work better but the higher the leakage in a transistor, generally the higher the noise. Transistor noise is critical with Q1, noisy Q1 = noisy circuit.
I found that a low leakage transistor works well for Q2, and what worked for me was one with a gain of around 100-110. I still need to try lower and higher gains for Q2 to see what that does to the circuit.
Q3 also needs to be leaky, I found a leakage of about 100-150ua works ok. I like a lowish gain also, like around 80-100. The higher gain Q3 is, the less range the attack knob has. In other words, the higher the gain of Q3, the less "gating" range is available. As for Q3 leakage, it needs to have some but not too much. The more leakage Q3 has, the lower the voltage will be on the collector of Q3. Most everyone says a Q3c voltage of 8-8.5 is desirable, which makes sense because if Q3c voltage is lower, like in the 7s, Q3 won't gate much, which I found to be true.
Also, a log or audio taper pot would probably be more versital for the attack control, more gating range on the attack knob.
This circuit still needs a lot of time spent to get the correct combination of things so it sounds good. I'd have to say that transistor gain, leakage AND noise are the big three factors determining how the MK1 will sound. A lot of the variance in opinions across the internet may be because of individual taste in sounds, but this is pedal building, so who knows...
Lol!
Well, I built mine and here's a few observations that I've made... Hopefully this will help other builders:
I found that Q1 works best if it has a gain of around 55-70, it also needs to be "leaky", like around 200ua. This is because the leakage is what biases Q1. A higher leakage might work better but the higher the leakage in a transistor, generally the higher the noise. Transistor noise is critical with Q1, noisy Q1 = noisy circuit.
I found that a low leakage transistor works well for Q2, and what worked for me was one with a gain of around 100-110. I still need to try lower and higher gains for Q2 to see what that does to the circuit.
Q3 also needs to be leaky, I found a leakage of about 100-150ua works ok. I like a lowish gain also, like around 80-100. The higher gain Q3 is, the less range the attack knob has. In other words, the higher the gain of Q3, the less "gating" range is available. As for Q3 leakage, it needs to have some but not too much. The more leakage Q3 has, the lower the voltage will be on the collector of Q3. Most everyone says a Q3c voltage of 8-8.5 is desirable, which makes sense because if Q3c voltage is lower, like in the 7s, Q3 won't gate much, which I found to be true.
Also, a log or audio taper pot would probably be more versital for the attack control, more gating range on the attack knob.
This circuit still needs a lot of time spent to get the correct combination of things so it sounds good. I'd have to say that transistor gain, leakage AND noise are the big three factors determining how the MK1 will sound. A lot of the variance in opinions across the internet may be because of individual taste in sounds, but this is pedal building, so who knows...
Lol!
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