#ring modulator

Ginean Ring Modulator

Death By Audio - RING-FUZZ

"Ollie [Ollie Ackermann, Death by Audio] made me a custom pedal back when Skywave was ending/APTBS was beginning ... Extreme fuzz with 5-position ring modulator. When the ring was activated, every knob changed its purpose. ...

[5 positions for] 5 different “frequencies.” You could activate just the Ring, and it would be changed with adjustments to the “synth” and volume…but you could also activate the fuzz as well, and then the ring could be adjusted with ANY of the knobs. You’d go from “sorta standard” ring sounds, to what I can only assume are the death rattles of HAL…

All at a volume level of insane proportions (it IS a DBA after all)… "

See, the circuit was a sine wave oscillator that worked by using a four-quadrant multiplier. The concept was that you fed an existing sine wave into both inputs, multiplying it by itself, and thereby got the two products of such a multiplication: a DC voltage and a sine wave at double the original frequency. (Strictly speaking, if the original is sin θ, the result is 2 cos θ, but you can ignore the phase offset. And the question of in exactly which circumstances you'd have a sine wave but need a different one at double the frequency is left as an exercise for the reader.)

But at any rate, in modular synthesis, another term for "four-quadrant multiplier" is "ring modulator". And when I tried it out, putting two copies of the same sine wave from my VCO into my ring mod, it worked like a charm: a new sine wave at double the frequency: that is, a note one octave up. I could mix it back together with the original wave to get the opposite of a suboctave.

So now I'm imagining some kind of additive synthesis setup — where you create complex waveforms by summing large numbers of different sine waves — where the components are created by banks of ring mods. Except I'm not sure of how you'd generate any other frequencies than powers of two of the originals, which probably limits the utility somewhat.

The United States of America LP (1968)