The only mechanical errors I see (6/26/2010 11:24am version) are 2 mis-spaces and a z/x slip.
line 4: look like aguitar signal
line 10: R1...R3 and C1...C3 determinethe feedback null
last line: All rights rexerved.
Hey, thanks for nailing those down. I noticed the "rexerved" as I posted it, but didn't catch the others. I'll go fix it.
Circuit looks to be drawn correctly. (I assume the twin-T inverts at center frequency? Too tired to work it out.) FWIW, the OUT jack is not marked as such.
Again, thanks. I did this in about half an hour; I have to finish things like this before I get pulled off to other stuff I have to do. Twin T has an infinitely deep null at center (if the Rs and Cs are tuned just right, these aren't perfect values) and a dramatic phase reversal at center. The null lets the opamp go almost open loop at center and the phase change does the rest. Single transistors make OK Twin T resonators and oscillators, although you have to be very careful with loading effects if you do that. PAIA did several variations of the Twin T as a ringing oscillator (bongos simulator) and resonator (wind/surf simulator) wah ( Poptronics article, 1969 I think), and fake "Leslie", the Synthespin, which was a Twin T resonator/wah driven by an LFO. It's quite flexible.
This thing owes its heritage to the drum simulators mostly.