AW: spikes (was:AW: FETs on the ASM-1 VCO.)

[Haible Juergen]

	>I'm not familiar with this - what does the variable shape function
of the
	>vcs3 do, and how ?

It's very simple: It's an ordinary one-transistor saw to triangle
converter, and there is a variable DC offset voltage that
will vary the point where the slope "folds over".
If you don't have perfect symmetry, there will always be 
a "jump" in the waveform. 
In theory one might think this is pretty useless, but it will
produce certain "trademark VCS3" modulations that
are very pleasant. You can hear it on the noise sound
at the beginning of this sample from my web site, for
example:

http://www.synthfool.com/diy/hj_adl4_turi.mp3

There is some filtered white noise, and the filter is
modulated with such an assymmetric triangle.
Once you know where this effect comes from, you might
recognize it on other recordings that use a VCS3, too.

JH.

PS.: Magnus, that might be an interesting addition for
you know what, too !