I've copy/pasted my entry here. Geek out!
Automatic Idiot FuzzSound clip: http://soundcloud.com/effdub/auto-idiot-fuzz-demoBriefly: This is a super simple LM386 nasty fuzzy front end with a cheap-n-dirty "envelope follower" (I use the term loosely) driving a twin-t (ish) type wah circuit on the output.
Long Story: I used the simplest, highest-gain configuration of the LM386 I could manage, which turns out looking an awful lot like the first part of the Clarinot, only with a pot to vary the gain. To make a crude envelope follower, I put some LEDs on the 386's output (clipped to ground) and paired that up with a typical LDR. There is a trimmer between the LEDs and ground to help set the brightness. This is a set-and-forget kind of thing, so I made it a trim.
The wah circuit is my take on Escobedo's Idiot Wah. I converted the "Resonance" switch to a pot to give more control. I call it "Vowel" because it shapes the type of vowel sound you get. I also changed up the filter caps to adjust the "sweep" to react more usefully with the clipping LEDs.
Overall it's not quite as quacky as I had hoped, but I still think it sounds cool. And it would make a nice thing to kick on during a solo to cut through in a band setting. It's got quite a bit of treble, so it's probably not good for standard rhythm work, but it would make a nice added texture in a layered rhythm part for recording. You can tune out a lot of the treble with the Vowel pot, but then you also lose the quack.
It won't replace your favorite fuzz or your best envelope filter, but considering the low parts count, it's kind of a neat one-trick pony.
Schematic Notes:• R4 knocks down the massive output of the 386. Without it (or something else doing the same thing), the circuit just sounds really bad and unusable.
• R8 sets the max value when the LDR is dark. I originally had a trimmer here, but 47K seems to be the magic number. The notes on the Idiot Wah say the resistance range for the "sweep" element should be 0R - 50K. The LDR I used goes down to 300R, and the 47K limits it to just under 47K when dark. But feel free to play with this value and see how it sounds. It also works when omitted, but it's a quackier with a limit in the 50K-ish range.
• C4/C5 act sort of like the max/min of a treadle position on a regular wah. Tune to taste.
Schematic:Attachment:
AIF_Schematic_V2-1.png [ 7.14 KiB | Viewed 7903 times ]
Improvements:Obviously, a better envelope follower would drastically improve things. Decay can't really be controlled with this circuit, and that makes the wah-ness less pronounced. I think it might be possible to rig up the diodes in series with the output and add an R/C time control, but the fuzz tone would likely suffer since that would generate crossover distortion.
I will continue to work on this general concept. I just wanted to submit something functional and tidy for the contest.
Login
Register
FAQ
Search
Great work as always.
