My design, still tweaking.

[Goodrat]

http://www.aronnelson.com/gallery/main.php/v/diyuser/Goodrat/Fuzz4.jpg.html?g2_imageViewsIndex=1

[Goodrat]

I just realized the "Pre-Tone" inductor should have a large cap in series to prevent DC from depleting the battery too quickly.

[slacker]

Looks interesting. Welcome to the forum

[askwho69]

fuzz or distortion? they are different in sound right? by the way! very intersting? sound clips?

WELCOME

[ayayay!]

Where are the tone pots going?  Ground or Vb?  ...Oh wait I get it.  You're connecting the outer lugs to the wiper, like on the Drive & Distortion pots. 

Why use inductors?  And do you have a part number/source for them, being 100mH? 

Thanks for sharing? 

[Goodrat]

I have some toroids that I've used for other purposes, so I thought I would give them a try to vary the low frequencies rather that vary the highs.
I wind near 100 turns to get 100mH. I'll look into part suggestions. I may just use one inductor after the distortion (after trying some other tone control designs).
I like using LED's. More smooth with even order harmonics.
I would delete this schematic in favor of what I've changed so for. (How to I delete??). For example, that is not a good way to shut off the distortion channel.
I have an original that I built gutting out a Sans amp (without the inductors) but left the preamp and it sounds awesome. I'm getting too much squealing. However it turns out it is just long wires and proto board problems. I'm getting close to final values. I think the goal is to cut below around 300 Hz on the first op amp and below about 1500Hz on the second after deciding on how much gain for each. (Gain of 10 on the first and 500 to 1000 on the second). Lots of great pick harmonics on my guitar and a nice clicky thump when palming the strings is what I'm after. Pus a good clean setting that is bright and clear. I can't seem to get a good clean sound without the buffer. I also can't seem to get the sound I want using non-inverting.

[merlinb]

http://www.aronnelson.com/gallery/main.php/v/diyuser/Goodrat/Fuzz4.jpg.html?g2_imageViewsIndex=1

You might want to reduce those resistors at the +ve input of each opamp to a few k-ohm, or eliminate them entirely, as they will be adding plenty of noise.
Also, the first opamp is driving the 470 ohm input resistor of the second stage, and may struggle. But then, such distortion may be part of the sound you want!

[Goodrat]

Reduce the 100K's on the bias you mean?
Here is today's revision. I want to try a non-inverting first stage to see if I can do without the buffer.
The inductor is a nice sound option and a pot has not much use on it.
The low resistance into the second stage I just seem to can't do without. But I will play more.
http://www.rickviola.com/images/Fuzz4.jpg

[Goodrat]

Every diagram I've seen had resistors at the + inputs before connecting to the bias. I'm pretty sure I get no output when eliminated, so how do you mean?
Also, I like to keep all pots the same and the gain near 1000 for the 2nd stage. I suppose I can try a higher feedback resistance in the second stage and increasing the input resistor, but I will probably introduce more noise with the higher feedback value and I most likely have tried that. It may be like you say, that the distortion caused by the low resistor is part of the sound. But I have to observe good layout and short wired, or else I get lots of squeal.

[Goodrat]

OK, here it is. It sounds perfect.
That coil switched in gives a nice tube sound. Not sure why. Any near 100mH coil should be ok.
Also, every time I use a TLO82 (drawing says TLO72, I never tried one), I find I need to tweak on of the bias resistors for even clipping on top and bottom when feeding with a sine wave gen and scoping the clean output. The bottom wants to be 130K vs the top 100K.
I may just add a switch on the 1uF after the first amp for about 4.7uf for bottom end selection and may be a cap at the volume control for a bright switch. The grounding of the distortion channel bias helps to cut it during clean mode. Not as perfect as disconnecting it but worth a try.
I'm not sure if that would be less noisy than just disconnecting the 1uF input cap at pin 2 for example).
http://www.rickviola.com/images/Fuzz010211.jpg

-Rick

[Goodrat]

Proto mess
http://www.rickviola.com/images/P1020003.JPG

[deadastronaut]

any soundclips?...

[merlinb]

Every diagram I've seen had resistors at the + inputs before connecting to the bias. I'm pretty sure I get no output when eliminated, so how do you mean?

I mean use zero ohms (direct link) rather than use a resistor.

[Goodrat]

I'll get a sound clip soon.
I'm making a few tweaks to the values.
Yes, the resistors are not needed fed to the bias. I hear noise go down a little too.