See below for notes.
Dual VCO schematic - panel
Noise Generator schematic - Random Clocks schematic
Dual AR Envelope generator schematic -
Dual Multiplier schematic - panel
DC Mixer schematic - panel
Triple LFO & Triple Sample/Track & Hold schematic
Dual Composite VCA
Dual Instrumentation Amplifier
Dual State Variable VCF
Full Wave Rectifier & Convolutors
..... and many many more!
I'm finally getting around to building my own modular synth.
I spent so much time designing and testing very fancy and complicated (expensive!)
modules, but never got around to actually building any of them.
For instance, the first VCO used a thermally heated matched pair (µa726),
a high end chopper FET (2N4857), provided for ramp, pwm, triangle, sine,
hard and soft sync,
linear FM, high frequency compensation for bulk emitter resistance in the
Too complicated. We used to have a lot of fun with an old Synthi AKS, which
used to drift
all over the place. Time to reconsider.
I've designed this stuff with cheap albeit older parts, no specially matched
garden variety FETs, in other words, stuff on hand.
The panels are 4 x 10" hobby aluminum from K&S Engineering, available
Forget etch primer, six coats of enamel, and silk screening. I'm lightly
the panels with 00 steel wool, and applying a self adhesive laser printer
Stackable bannana plugs.
Please find attached the schematics, and some panel examples. All circuits
have been breadboarded,
and are being built as shown, subject to small changes here and there.
Feel free to distribute freely, but please credit the author. Any comments