Differential Distortion build

[jmusser]

I built this sometime last week. It's at http://muzique.com/schem/diffuzz.gif I had heard it was a pretty good, but I wasn't overly impressed with it. I used a couple mods off of Frank Clarke's and Stellan's sites. One of the first things I did, was sub the 1K at the collector of Q3 from 1K, to a 100K, although it could easily be a 47K. The main thing is, it has to be several times bigger than the 1K to get any volume at all. I figure this is just a design glitch. I added the 10 Meg and SPST switch off of Q3's base for what Frank calls " bias weirdness".  It gives the circuit the circuit more growl for rythmn. I also changed the 6.2K to a 10K pot off of the emitter of Q1 per Stellan. It's supposed to change the level of distortion, but it basically seems to change the biasing, so I just leave it in the sweet spot. I'd guess that sweet spot is 6.2K, just like the fixed resistor that was in there to start with. A 2N5089 in the Q1 position instead of the 2N5088, helps define the distortion a whole lot better in my opinion. It's not a bad sounding circuit, but I believe every other one I've built so far will out do it in tone. The Mockman comes to mind. If anyone has any ideas for making it sound better, I'm listening.

[squidsquad]

Jeffarroo!

FINALLY...a subject I can ramble about...if you pardon me repeating an old tale. 
Ain't that what old men do...repeat stories?

On my Diff Dist....I accidentally shorted the 6k2 to ground...liked the sound better. 
Brett put a 10uf polarised cap to ground there and a couple other changes.
(shown here:  http://www.members.optusnet.com.au/~jethro.dog/gallery.html)

I used a 100k trimmer on the Q1 collector.  Used a standard pot mounted outboard...because the sweet spot drifts w/battery voltage....and you can dial it in...& also tell when the batt is dyin because it will move away from the normal position.

My output was low also...so I tacked on a Fetzer Valve & then had PLENTY of gain.

Also...by shorting that resistor...the input cap was too large...WAY too much compression.

So I used a 2 pole switch...to choose between a .001 (still a fuzz but leaning towards treble boost)
and a .012 (fat w/bloom).  VERY crtical there...tried lots of values.

Ummm...I also tacked a cap across the output to reduce high end hash.

Sorta like a Frankenstein Fuzz (nice name eh?)...pieced together & ressurected.

I always like the sound of it....so it earned an honored spot in a recycled big EH sheet metal box...hehe!

[jmusser]

Hey Squid, thanks for the link and the mod info. I want to give it a chance to sound as good as it can. I believe that's the first one of Brett's links that I've actually been able to get to. He has a lot of nice stuff over there.