Re: analog sound demonstrations

[James Beauchamp <jwb@xxxxxxxxxxxxxxxxxxxxx>]

Gregory Kramer:
>Jim Beauchamps answers seem reasonable but carrying around a NeXT is the
>kind of thing Richard wanted to avoid.

Actually, carrying a NeXTStation and display around is not any more cumbersome
than say a MiniMoog plus an oscilloscope. Note that the NeXTs each have a
56001 DSP chip in them so that synthesis is real time.

>Analog oscillators and mixers are easy enough to build.

But getting analog oscillators to synchronize ( fk = k*f1) with variable phase
is not so easy. I made a six oscillator set in the 60's where harmonics were
generated in the ultrasonic range and heterodyned down to audio. It had
voltage-controlled harmonic amplitude and fundamental frequency controls.
Don Buchla built one in the late 60's or early 70's, but I don't know how well
it operated.

Jim Beauchamp