Negative frequency

[jh.]

> The original Yamaha DX-7 was a mono FM synth. Several of the better DX-7
> organ patches simulate the Hammond B3 organ sound, but not in stereo. They
> did it by modulating 6 sine wave VCOs in a particular arrangement. What
Don
> was explaining was that the CV inputs of some of those oscillators
actually
> go between negative and positive CVs. This causes some VCOs to go quickly
in
> and out of phase with eachother causing the shimmering Hammond sound.

I thought Don was referring to these patches where a fixed frequency
(usually 1Hz)
oscillator serves as carrier for all the rest. The effect is very nice
indeed; the only
drawback was (if memory serves) that the operators couldn't go down below
1Hz.

JH.