Author Topic: High gain Jfet fuzz  (Read 3619 times)

night-B

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High gain Jfet fuzz
« on: April 06, 2012, 05:04:09 AM »
Hi guys!
I'd like to make some experimentations with my own design of fuzz.
I've got a question. I'd like to try using Jfets like the J201 and adapt it to circuit close to the fuzz face or maybe a tonebender. Since the pinout is completely different, do somebody know how to use them before I tweak the circuit on the breadboard?
Thanks

stecykmi

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Re: High gain Jfet fuzz
« Reply #1 on: April 06, 2012, 11:07:34 AM »
JFETs are significantly different than BJTs in their biasing requirements. You could definitely build something with a lot of the same topology, but you'll need to change the bias network a lot. It's my guess that it probably won't sound that much like a typical fuzz face circuit (not necessarily a bad thing).
« Last Edit: April 06, 2012, 11:13:52 AM by stecykmi »

night-B

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Re: High gain Jfet fuzz
« Reply #2 on: April 06, 2012, 11:19:44 AM »
I thought it would sound different and interesting. I just don't know what is the equivalent for the emitter base and collector on these...

midwayfair

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Re: High gain Jfet fuzz
« Reply #3 on: April 06, 2012, 08:30:22 PM »
In much the same way that transistors were used similarly to some tube setups, so were JFETs:

http://www.runoffgroove.com/fetzervalve.html

Runoffgrove has some other useful articles like this ... You can also try Jack Orman's site for some ideas.

I'm thinking your future involves an awful lot of bias pots on your breadboard ;)
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