dry/wet signal blend for BMP

[ural]

Advice me please how to add signal blend to GGG BMP pedal. And what kind of blend should I use?

I'm use this pedal on bass and thinking that could be nice option to keep part of dry bass sound "unfuzzed".

[eatyourguitar]

runoff groove splitter blend. you can make your own PCB or build it on strip board from your own layout. there is a way to just use one TL072. take the input buffers from the splitter blend only. the output from one side goes to the BMP. then the BMP and the clean signal from the other buffer get mixed passively in a 50k linear knob. thats the blend knob. the outside lugs are the 2 signals you want to blend and the middle lug is the output.

[ural]

runoff groove splitter blend. you can make your own PCB or build it on strip board from your own layout. there is a way to just use one TL072. take the input buffers from the splitter blend only. the output from one side goes to the BMP. then the BMP and the clean signal from the other buffer get mixed passively in a 50k linear knob. thats the blend knob. the outside lugs are the 2 signals you want to blend and the middle lug is the output.

thanks! is it the same solution what f.e. Dwarfcraft Devices using in Dogs Hair?

[eatyourguitar]

I dont know. I never opened one up. you could ask in the dwarfcraft forum.

[McSpunckle]

Alternatively, you could tap off the input side of the sustain control. You could literally wire a second pot directly to it, and the output of that one could go to a unity gain booster-- the booster wouldn't boost, but it would match the phase and output impedance of the fuzz circuit.

It might not be totally clean, but it'll only be a little dirty.

[ural]

Alternatively, you could tap off the input side of the sustain control. You could literally wire a second pot directly to it, and the output of that one could go to a unity gain booster-- the booster wouldn't boost, but it would match the phase and output impedance of the fuzz circuit.

It might not be totally clean, but it'll only be a little dirty.

Thanks! Interesting.
Several amateurish questions:
Should I use 100k for that pot or different value?
Should I use any resistor in ground chain of that pot?
Do you mean by "gain booster" the output stage of pedal? Should I solder output of "wet/dry" pot to output leg of tone pot?

[McSpunckle]

Let me draw it up and scan it real quick so you'll get a better idea... I'm having trouble wording it in a way I think will make sense.

[ural]

Let me draw it up and scan it real quick so you'll get a better idea... I'm having trouble wording it in a way I think will make sense.

Thank you!

[McSpunckle]

Ok, so it turns out I don't know how to use my scanner. So I did a schematic in eagle.

Cleanmuff.png (1.23 KiB) Viewed 2470 times

I used a MOSFET circuit instead of the typical LPB because it has a higher input impedance and won't load down the Big Muff significantly.

The 500K pot could realistically be 1M, too. And the 2M2 resistors could be whatever as long as they match, but I wouldn't go below 1M. The 10uF cap is probably overkill, but they're pretty tiny these days, so I use them for outputs when I want to keep all the bass I can.

The input is connected to the input of the gain control, and the output is connected to either the input or output of the volume control (depending on if you want the volume to turn down the clean or not).

What I meant by "unity gain booster" is that the circuit is normally a booster, but it's set up where it doesn't boost. In this case, it looks like an SHO with the gain turned all the way down and a volume control in front. So it's basically acting like a buffer, but with the correct phase and output impedance.

You don't want a resistor to ground on the pot because then you couldn't turn it all the way down.

You could easily use any LPB perfboard layout with a slight modification.

[ural]

Ok, so it turns out I don't know how to use my scanner. So I did a schematic in eagle.

Cleanmuff.png

I used a MOSFET circuit instead of the typical LPB because it has a higher input impedance and won't load down the Big Muff significantly.

The 500K pot could realistically be 1M, too. And the 2M2 resistors could be whatever as long as they match, but I wouldn't go below 1M. The 10uF cap is probably overkill, but they're pretty tiny these days, so I use them for outputs when I want to keep all the bass I can.

The input is connected to the input of the gain control, and the output is connected to either the input or output of the volume control (depending on if you want the volume to turn down the clean or not).

What I meant by "unity gain booster" is that the circuit is normally a booster, but it's set up where it doesn't boost. In this case, it looks like an SHO with the gain turned all the way down and a volume control in front. So it's basically acting like a buffer, but with the correct phase and output impedance.

You don't want a resistor to ground on the pot because then you couldn't turn it all the way down.

You could easily use any LPB perfboard layout with a slight modification.

Thanks again! I'll try.