[sdiy] Best software noise algorithm?

[Tom Wiltshire]

On 17 Feb 2010, at 20:01, Scott Nordlund wrote:

>
> Certain older digital synths had some interesting ways of faking
> "noise".  The Casio CZ series and Yamaha OPL chips seemed to do
> some sort of crazy phase modulation feedback, and the Ensoniq ESQ-1
> used nasty single cycle waveforms with the recommendation that they
> be pitch modulated for lots of aliasing.
>
> But I'm sure these are not efficient OR spectrally pure.  Probably
> less irritating than the MM5837, anyway.

Ah, yes! That's another approach I hadn't thought of. It's true that  
if you do an FM(PM) feedback loop on a oscillator, the number of  
sidebands increases to the point at which you've got noise. And I  
don't suppose it is spectrally perfect, but I'm not being fussy.

So - can it be done in better than 19 cycles?! It's almost enough of  
a challenge to do it just to see...

Thanks,
Tom