Good sound but whining noises...

[Sam]

Being the huge "Bazz Fuss" fan I am I often find myself looming over the circuit mounted up on the breadboard.

I set up a Buzz Box and tweaked it. I changed Q1 to a darlington BC517 and made both diodes silicon. Then I started to stick bits and pieces from other circuits in there. Suddenly I was playing this very thick, smooth and powerful octave up fuzz. It has this extremely pronounced second harmonic but isn't harsh or sharp sounding and the sustain is very good, with a hint of animation to the sound. Like a 'rounder' and 'fuller' Buzz Box.

The only problem is the whining feedback i get, and there is just to much output. I tried all the tricks I've read about concerning oscillation (here and on all the other great pages, thanks BTW!). I'm able to get rid of the oscillation but doing so most of the great octave-up effect is lost to.

I really want this to work. Please help.  :cry:

I'm currently at work and forgot my sketches at home, so drew this schematic from memory... Can't remember the exact value of some of the resistors.

Schematic:
http://i2.photobucket.com/albums/y8/JSam/Something.jpg

[Sam]

BTW, as soon as I get all the exact values I'll post them.

[Sam]

I know, it might not be easy to help based on uncompleted sketches. I'll post a few pics and soundclips soon.  

[rodriki1]

Hi

The gain here is pretty high.

I think you have already tried to put a low value
colector to base capacitor.

Other thing.

You will have to decrease gain.
You can do that by putting one resistor between
emitter and the parallel resistor/capacitor that goes to the ground.

The emitter to ground capacitor gives the high gain.

After that add put another booster stage in front of circuit.

hope this help.