Behringer UZ400 Ultra Fuzz transistor modification

A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence.
Post Reply
User avatar
manubigana
Information
Posts: 1
Joined: 04 Jul 2016, 01:16

Post by manubigana »

I want to change my Behringer Fuzz UZ 400 to get a more vintage tone.
It use a silicon transistor K184/GR7C.

Which germanium transistor can I put in it? Or not?

User avatar
mictester
Old Solderhand
Information
Posts: 2923
Joined: 11 Sep 2008, 20:29
my favorite amplifier: Mesa Boogie, Roost Sessionmaster, AC30
Completed builds: Hundreds! Mostly originals, a few clones and lots of modifications.
Location: Somewhat closer to Amsterdam than before!
Has thanked: 32 times
Been thanked: 844 times
Contact:

Post by mictester »

You can't just change the transistors. All the resistors would need to be changed too, since silicon biases completely differently to germanium. You can improve the tone of a silicon fuzz face by adding low value base to collector capacitors at each transistor. Start with (say) 100p and try increasing each one until you get the tone you want. In most situations, especially a band situation, a modified silicon FF is indistinguishable from a germanium one - except that the output will be louder.
"Why is it humming?" "Because it doesn't know the words!"

Post Reply