DIY Blenders

[speak_onion]

Ok, so I am working on blenders for my dist/od, my fuzz, and possibly my bass synth. I built the Buff'n'Blend, and it worked ok with my OD, but when I put anything really high gain into it (Devi AR SM, DOD FX86B), I could tell that it was feeding back. I don't mean that it's causing amp feedback, I mean I recognized the sound of the FX86B in a direct feedback loop, because that's what I normally use it for. I checked it over and over again, and I can't find any mistakes, and based on the schem, it's not unreasonable to me that the circuit could have some inherent feedback. Maybe I'm wrong.

Ok, so here comes my question:
For those of you out there who have made blenders, what circuits have you used? I'm aware of the Miniblender, and the B-Blender. I have everything needed for the Miniblender around, so I could breadboard it and see what's what. . . I think I'll order the parts for the B-Blender today, since I have a 15% off coupon for newark.com that expires after today. Mostly I'd just like to know what circuits yous all are using on your DIY Blenders. Thanks.

[speak_onion]

Upon more research at diystompboxes, it seems like the B-Blender is THE circuit to use. I'd still love to hear what yous all have to say.

[tommy.genes]

The reason the B Blender works without feedback is because it has an active buffer in the blend path so audio only "flows" in one direction. A passive blend path has the sometimes unintended side effect of being a feedback path as well.

The 90% B Blender is about as simple as you can get and still meet this minimum requirement. If you really don't want to use opamps, e.g. you want to use only parts that you already have, use the FET substitute shown on the same page. You could also graft the FET substitue into the Buff'n'blend schematic if you want a pre-buffer as well.

BTW, Sean M is sometimes active here as well as at diystompboxes.com if you want to ask him any questions directly.

-- T. G. --