Variable ramp again

[mbartkow at ET.PUT.Poznan.PL]

Don Tillman <don at till.com> wrote:

> This makes a great thought experiment, but it won't work in practice.

Well, in fact it IS really working on my desktop :-)

> As a thought experiment it tells us that the sound of a variable duty
> cycle sawtooth is going to be like a PWM square wave through an
> integrator, adjusting for level and offset (which we can do also do in
> our head).  The harmonics will all be the same as a PWM square wave,
> there will just be fewer of them.  Great.  Not a breakthrough or
> anything, but at the far end of the range those buzzy thin little
> pulses will now sound like fat sawtooth waves, making me think it has
> a lot of potential.
>
> But the real interesting things happen when we dynamically modulate
> the duty cycle, or FM modulate the duty cycle with an audio source, or
> cross modulate a couple of these ocillators. [...]

It has been discussed already. I repeat, it's the SHAPE of the wave, not
the timbre, since I need it for waveshaping purposes. It is a breakthrough,
because a PWM pulse wave cannot be waveshaped. 
And talking about VR sonic advantages over PWM, the main one is that it
keeps constant AC power as the ramp ratio changes, contrary to pulse wave.

And yes, of course I consider audio rate modulation as a source of much more
interesting timbres than PWM offers.

regards,

MB