PedalPCB Soul Vendor/Fulltone Soul Bender

[OD is Glorious]

Build Rating

5.00 star(s)

Sounds like a sustaining saturated fuzz. The controls are useful and the dirt potentiometer works perfectly to bring the honey bees or the murder wasps. I think as far as fuzz goes, it is decent. This circuit with the MP26 transistors does not have flub or gating: it just has magnificent distortion or sustaining fuzz.

In my experience this tone knob works different in that turning left gets treble. Build docs call for three B100k potentiometers but I used B100k for dirt and tone and I used an A100k for the volume. I used a 1N270 Ge diode and a TC1044 charge pump. Instead of the hard to find (PNP) NKT275 Ge transistors I ordered ten (PNP) NOS MP26b transistors from Ukraine. I spent hours trying to measure and finally I just socketed them on the pcb. I settled on the first three I tried because this ain't diamond cutting - it is a fuzz and all it needs to do is please my ears. So it does please them.

I used a Tayda pastel green 125b with a film free decal and a Spraymax 2k clear coat. I used some 19mm red fluted mirror cap knobs. I used top jacks with a PPCB top jack faceplate. Inside I used enclosed mono jacks and a soft click footswitch.

If you love fuzz you will probably have to build one

Notes

1. NKT275 are hard to find. Other Soviet era transistors will work great- if testing is hard socket them and try, try.
2. I think an A100k works great for volume
3. Tone knob works counterintuitively
4. Lots of room in a 125b which means this will easily fit in a 1590b if you mind the height of components

 

[bluedmc777]

I actually have an old Madbean board for this I’ve been meaning to get too. I’ve found a few guys shots online of the actual pedal and it appears he uses pretty low gain transistors. 76 being the highest in what I assume is Q2.

 

[OD is Glorious]

I got ten MP26 and made myself crazy tring to test them with a breadboard and multimeter so i just put these in and they were perfect straight away. I know you were going to make one... what are you going to use for the three NKT275? I think these MP26 sound terrific.

 

[bluedmc777]

I have some low gains with hfe ranging from 50-70s with low leakage that I got specifically for this project but I have some higher gain as well. I’ll probably just mix them until I find rate sounds good to me. I almost forgot you printed those labels for this one for me lol.

 

[OD is Glorious]

I have some low gains with hfe ranging from 50-70s with low leakage that I got specifically for this project but I have some higher gain as well. I’ll probably just mix them until I find rate sounds good to me. I almost forgot you printed those labels for this one for me lol.

What exact ones did you get?

 

[bluedmc777]

I’m not even sure of the exact part numbers I bought some from Joe at JDM pedals because he knows how to test them properly and which sound good in the different circuits. https://www.joedocmusic.com/category/jdm-pedals/ For PNP there’s a mixture of AC128, some Russian ones that I don’t know off the top of my head, some ACY ones and a couple others of Chinese ones. I bought a good bit of PNP and NPN from him. I just tell him what hfe and leakage I’m looking for.

 

[OD is Glorious]

I’m not even sure of the exact part numbers I bought some from Joe at JDM pedals because he knows how to test them properly and which sound good in the different circuits. https://www.joedocmusic.com/category/jdm-pedals/ For PNP there’s a mixture of AC128, some Russian ones that I don’t know off the top of my head, some ACY ones and a couple others of Chinese ones. I bought a good bit of PNP and NPN from him. I just tell him what hfe and leakage I’m looking for.

Those AC128s were hard to find as well. I have not tried them but I can say the MP26s sound great in this circuit. I am interested to hear your thoughts after you complete the circuit with your selections.

 

[bluedmc777]

Yea I’m curious as well. After reading all of the build reports, and there isn’t many, it seems like it’s a hard one to dial in and that the tone control isn’t very effective

 

[OD is Glorious]

Yea I’m curious as well. After reading all of the build reports, and there isn’t many, it seems like it’s a hard one to dial in and that the tone control isn’t very effective

The Tone works great, just backwards. I like it around noon, but it gets pinched and high all the way left, and low to the right. It is pleasing but counterintuitive. Be prepared for long sustain and tight clipping. As far as fuzz goes, it may not be unique but it is pleasing.

 

[Bret608]

This is based on the MkIII and MkIV Tonebender family. Q1 and Q2 form a Darlington to push Q3, so they can be lower gain/leakage. Q3 on this works better if leaky (higher gain doesn't hurt but isnt totally necssary). In fact that position has to have either the diode or transistor leaky to bias and/or pass signal. Overall though, it's one of the more forgiving fuzzes and it's hard to get it to sound bad. I've done a few and usually go 40-60 hfe for q1 and 2, then 100 or more for q3.

 

[OD is Glorious]

This is based on the MkIII and MkIV Tonebender family. Q1 and Q2 form a Darlington to push Q3, so they can be lower gain/leakage. Q3 on this works better if leaky (higher gain doesn't hurt but isnt totally necssary). In fact that position has to have either the diode or transistor leaky to bias and/or pass signal. Overall though, it's one of the more forgiving fuzzes and it's hard to get it to sound bad. I've done a few and usually go 40-60 hfe for q1 and 2, then 100 or more for q3.

Thanks for the opinion about the the components and the circuit. I agree with you after my limited experience with the circuit.