Dunlop - Eric Johnson Signature Fuzz Face EJF1  [traced]

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polifemo
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Post by polifemo »

Skreddy wrote:I use the standard 33k emitter resistor for Q1
Q2's bias is set thusly: an 820R to 9v, which is where I tap the output signal to the volume pot (and I use a .047uf cap to make a 100k pot sound the same as a .01 cap into a 500k pot) and a 1.8k resistor in series with a 10k bias pot.
Thanks.

I've been going for more of a "distortion tone" this time using 43k for Q1 (1,2v) and biasing Q2 somewhere between 5v-6v. I also ended up with BC109c's (hfe at about 500) in both positions whereas I'd normally have a BC109b in Q1.
Some additional tweaks here and there and the pedal do sound great, but your fuzz sounded much better.
Really nice tone shaping, a great focused fuzz character and very well thought out features.
Congrats to a great pedal :applause:

Now back to the EJ Fuzz! (sorry for the hijack...)

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angelodp1
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Post by angelodp1 »

Very useful info for an EJ fuzz. Why not use the Sunface route with the trimmer up top? Any downside to puting in a 5k or 10k pot that has a place up top?

A

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yeeshkul
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Post by yeeshkul »

So what is that cap across the feedback resistor for again? And why did you guys omitted it from your EJ FF schematics?

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Chris Brown
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Post by Chris Brown »

It's been a long time but I think was a HF rolloff to prevent oscillation

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