[sdiy] Analysis of frequency variation in analogue synths

Mike profpep at hotmail.com
Thu May 3 17:19:56 CEST 2007

I am about to try a similar  experiment, thanks to the help of Ingo Debus. I
had a home made organ/poly thing I made in the 70's. It used a frequency
combining technique to generate the top octave, which needed division by
256, to smooth out jitter. The design being from 'Elektor' magazine, which
Ingo kindly provided a PDF copy of. In my gadget I only divided by 16, and
then allowed my voice card to do the rest, resulting in some wave jitter in
my hybrid voice modules, (I was stepping through 16 slider pot derived
voltages to  allow me to 'draw' waveforms, and idea inspired by the late
great Dphne Oram's "Oramics" system).  I can't remember the sound now, and
have no recordings, but I was well pleased with a certain aspect of the
results, it seemed less clinical than the top octave chips I had tried, (it
also had a conventional divider organ section).

Again, I'm only looking to get a subjective handle on this, but I will
report back. I also hope that I can finally turn the 40 plus TTL chips of
the original into some kind of FPGA!


More information about the Synth-diy mailing list