Another contribution by Chris. This time he made some improvements and addons on a rare and wild Death by Audio circuit. Tone houndz...stay away!
Chris says:
I don't know if this warrants its own post but I wanted
to show it to you anyway since I was the one who verified your purple
card drawing.
Since I built
that up I wasn't happy with the bleed through in bypass that sometimes
happens with the LM567. So I used the old "millennium bypass" trick of
adding a mosfet to handle the LED switching so that you can use only a
DPDT for true bypass with an indicator light. THEN I used the now-vacant
set of poles on a 3PDT to connect/disconnect the power supply to the
LM567 when the circuit is bypassed. So NO NOISE! I also added the master
volume, because if ANY circuit needs it, it is this loud beast. Then I
put the frequency pot (which I cut down to 10k) on a switched expression
jack so that you can get foot-controlled crazy pitch-wah sounds with a
standard TRS expression pedal like an inexpensive m-audio or nektar
controller. Anything more than 15-20k of resistance for the frequency
control just takes you into slower and slower chopped/tremolo territory.
And the 10k pot still allows for some of that in the toe up/CCW
position and all of the pitch control as you turn the knob up/put the
treadle down.
I added a toggle to change the resistance on the frequency sweep - this
allows for a low range and high range mode on the frequency. Since most
expression pedals have 10k pots, I wanted to keep the frequency pot at
10k too so that the sweep matches whether you are using the knob or an
exp pedal.
