i had to get that out of the way...
always loved the os mutantes fuzz sound, so i found this:
which of course, meant i had to build one. so i did yesterday.
Updated layout is here: viewtopic.php?f=19&t=23239#p229184
other than a couple things in the BOM beneath being mislabeled, the layout itself is built and verified.
used next closest values in a couple spots, 3.9n for 3n, 2.2k for 2.5k , had to make a 3.3m resistor with a 2.2 and a 1m in series, used a 10k trimmer. built initially with bc547's, tried a gamut of silicon, and the fuzz part was great, but the treble boost part shrill and unmusical. i tried it as a hybrid, sounds great with bc109/108 pair, but in that case needs a cap to bleed off the shrill high end. there's quite a bit of tone for such a simple circuit... but i didn't want to deal with that unmusical treble, a shrieky kinda "presence" like on a marshall jcm800.. so i went germanium, with some vintage npn's a freind salvaged from an old thomas organ. that did it. brought the whole thing to life. so... sockets are your friends. i made this so you can use just one piece of SIP socket for both transistors. i used my iron to poke out the one between them just to make it idiot proof.
gotta wait to check the hfe's, my meter is down in the basement with another project.
also added simple standard power supply filtering, a couple diodes, a current limiting resistor and a bleeder and filter cap. since the unit already has a 47u filter cap on board, it's very quiet. i will add a 100u cap right across the power rails at the power jack too, probably overkill but i like fuzz pedals to be quiet as possible when not making some raucous fuckin' noise.
how does it sound? really good. different from almost every other fuzz i've built, with two distinct personalities between the filtered and fuzzed setting. one knob. volume. that's it. perfect for kamikazee studio here.
the treble boost side is vaguely klon centaurish tonally, with a hint of nasal mid sounding very much like an old marshall right on the breaking point, the fuzz side (bypassing the small "filter" cap) is big and wooly like a big muff and has a real nice sustain with a pronounced buzz to it. at least into an overdriven amp.
as with virtually all fuzz, it sounds like poo without hitting a somewhat distorted amp. but add it to a cranked up tube amp... and .... yum.
stupid pedal trick coming soon, for now tho, here's some os mutantes:
if you want the exact kinda sound in this video, use bc108 and 109. socket. experiment. you'll find it.
