The common method for generating a sine output from a VCO involves
taking the native waveform that the vco generates (usually a
sawtooth), then deriving a triangle (often with a small notch at the
peak), then using the derived triangle to drive a CA3080 into the
nonlinear region to approximate a sine wave. The key word here
is "approximate". It is not that pure. An oscillating VCF, however,
can generate a very pure sine wave. When I do FM and cross linked
chaos patches, I generally get better results when both modulator and
modulatee are oscillating filters.
Moe
--- In motm@yahoogroups.com, "foraxx" <omgemag@h...> wrote:
> I've heard that it is difficult for a VCO to create a sine waveform
> (or really a good quality sine wave). Is this true and why is it
> so? Its obvious to me that it would be harder to generate a sine
> wave in comparison to a square wave, but what is specifically
> challenging theoretically and in practice?