JH's VCO, wavetable source, variable ramp

[mbartkow at ET.PUT.Poznan.PL]

harry bissell <harrybissell at prodigy.net> wrote:

> :^) I'm still not convinced. There are many "geometric" shapes that look different to
> the Human Eye that have exactly the same harmonic recipe (amplitude). That leaves
> "phase" and the ability of humans to hear that in the frequency domain (20-20KHz) is
> still debated hotly. Filtering probably won't change that.

While this is perfectly true, I don't consider those simple geometric shapes
as a final VCO output signal. As I previously said, I just want to apply some
advanced waveshaping instead of mixing basic waveforms. Believe me, I know
how to get very interesting timbral changes by twisting a simple triangle
or saw waveform. Now, consider nonlinear shaping circuit being extremely
sensitive to the shape of the input wave. I have spent many ours on simulating
these in CSOUND and figured out that changing the symmetry (the ramp ratio)
is probably the most efficient way to achieve drastical changes of the sound.
I repeat, I heard the differences, not only observed the plots.


> I thought the VCS3 had variable ramp or was that some other unit ????

Indeed, I heard about it. I don't have the schematics, though. Maybe
Juergen would help here ?

regards,

mb


--

Maciej Bartkowiak, PhD
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