ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

Fuzz Face=square wave?

:

5/2/1999 1:13 AM

Fuzz Face=square wave?

When I hook up my diy Fuzz Face to a scope I get a square wave.Also, when I do a simulation using EWB, I get the same square wave. Is this what I should be seeing, or should I be tweaking components to round the edges? When all you guys talk about a good sounding FF, I picture more of a squashed sine wave without any sharp edges. If someone would shed some knowledge on this I would be very grateful.
Stan

5/2/1999 2:15 AM
aron	Check out this link. Everything you wanted to know: http://www.eden.com/~keen/fffram.htm Aron

5/4/1999 5:39 AM
GFR	You can see some osciloscope screens (and sound samples) of a bad and a good FF on http://www.geocities.com/SunsetStrip/Studio/2987/ Go to the "Brit Face" section. If you drive the FF too hard, you'll get a square wave. Try lowering the input signal level and you'll get soft, assymetric distortion.

5/5/1999 9:50 AM
Stan Bailey	Man, whats up with ampage, it's taken me forever to log on. Anyway, thanks for the info guys. I am putting a 1K 80mV(peak) sine wave through it. It definately is a asymetrical square wave with EWB as well as the FF to a scope.I am pretty new at interpeting waveforms (obvious I'm sure). In general, would one want to see a asymetrical type of sine wave to achieve smooth distortion? Thanks, Stan

5/5/1999 10:13 AM

try a 10 resistor in series with the input of the FF. The feedback resistor from the emitter of the 2nd tran to the base of the 1st works with the Z of the pickup coil to set the gain ( the overall gain is set by the 2nd transistor gain control x the feedback R/in z) that is one reason the ff circuit has more bass than treble the in z increases with freg. that is also why the Fulltone two tran FF type circuits can work before or after a stock Wha circuit. A test bed signal source tend to be low Z with would be a very low z in gain would be very high. FWIW I use a 10k pot in series with my HP osc to effects when I test them on the workbench.

5/5/1999 3:24 PM
Stan Bailey	Thanks Gus, very well explained! Your info jives with what I am learning in school. It feels great to understand what the circuit is doing, opposed to just building it. Thanks, Stan

Page 1 of 1