Anyone recommend a Fuzzface project using 187/188s?

[niftyprose]

Hi guys, the subject line says it all. I'm having a clearout and I turned up a NOS matched pair of AC187/188 germanium transistors that I didn't even know I had. My semiliterate response was of course to consider a FuzzFace, but I'm aware that these might not be first choice for such a project. Is anyone aware of a good fuzz project for which they'd be suitable? Best, NP

[frodog]

I'm not an expert but have a few different fuzzes under my belt... The first thing that comes to mind is a Harmonic Percolator, which calls for a PNP/NPN pair. The AC188 would definitely fit as the PNP (I have one on breadboard now that uses AC128) although the NPN transistor is usually silicon (2N3565 or any number of more common ones will work) in the HP?

I guess it's fully possible to use germanium if you really want to use them both, but results may vary. I would experiment on breadboard first to tune the gain of the PNP, get enough volume from the NPN, try different diodes and such. If you don't want to do that or want to go with a kit, I'm pretty sure the 188 would be alright (assuming it's healthy) but for the NPN I'd go with the more standard option(s) or in any case socket and see.

Take this as advice from an amateur, not-electrically-trained builder

I've been going by this layout btw: http://tagboardeffects.blogspot.com/201 ... lator.html

[niftyprose]

Thanks, Frodog, that's brilliant advice -- I *didn't know* about the Percolator (shuffles...).

[frodog]

No shuffling required, I also had never tried a Harmonic Percolator until I built one like half a year ago. Before then I had heard it mentioned here and there but never expected it to be so rad and versatile. I wanna try to build at least a couple more because there are a few variations out there and ample opportunity to customize it beyond the standard.

[eatyourguitar]

you can build an up and down fuzz. two fuzz face circuits in parallel. one NPN one PNP. they are both asymetric wave shapers but they fuzz opposite sides of the waveform. I tried to do this once but there were significant challenges with phase, input impedance, does it work at all, does it sound good. never finished it. could be a waste of time. could be awesome.

[Bret608]

I noticed DeadEnd FX put out a Percolator board (look for the Splinter)...it has a big enough footprint to use a germanium for the NPN, and they do recommend trying it out. I haven't tried that setup myself but I bet it would sound good! I have a "stock" specs version I still need to box.

Other than that, I think the Spaceman Gemini fuzz circuit would be a place where you could use both of these. DeadEnd sells boards for a couple versions of that circuit I think.

[eatyourguitar]

how about a germium push pull amplifier? that would probably make an interesting gain stage when overdriven.