ISO: Looking for a (BC108 related) Fuzz Layout with a Gain control

[Hendrik1]

Looking for a Fuzz Layout with a Gain control,
I am going to use BC108 in search for the Jimi sound.

Thanks in advance.
H

[MartyMart]

http://aronnelson.com/gallery/album17/SILICON_FUZZ_FACE

Try this, seems to have worked out for others with BC108's
There's lots more in Andy's gallery too

MM.

[Hendrik1]

Thank you Martymart

[JHS]

BC108 comes as A,B or C type (w/o letter it is allways C) and w hfe from 200-500, for the schem in the layout the B type is needed (due to the 33k R) to get correct bias voltage on the base of Tr2. Even the B types stray a lot, so try at least a few or use a 47k trimpot for the 33k and a 22k trimpot for the 8,2k for voltage adjustment. The B type is OK, the C type can produce oscillation due to the higher gain.

Other Si-trannies like BC109 work well but the BC108 produce the most agressive sound of all trannies I've tried so far.
The original old BC108 is hard to get and sounds a bit different when compared to newer ones.

The Colorsound Fuzz is nearly identical, but have BC182L or 173 in it for a smoother and middier sound.


JHS