commercial synth circuits

[Tony Clark]

> I cant quite see why one has to discharge the integrating cap in one hit..
> wouldn't it make sense to integrate up and then down at the same rate, to 
> give a triangle instead of a sawtooth? Isn't this how it is usually done?
> Admittedly, one now has to make a sawtooth from a triangle instead of 
> vice-versa, but this is no worse..

   Well that depends on how you do the transformation.  In order to keep 
the frequency the same, you have to invert the down-slope of the triangle 
wave and then offset BOTH parts in order to create a saw wave.  You then 
tend to get two sets of glitches, one at the mid-point of the saw wave 
and one at the reset.  At low frequencies, the glitching is unacceptable 
for LFO use.
   Now if you were just inverting the down-slope and creating a 2X freq. 
saw, then it wouldn't be so bad.
   Just my observations.

   Tony

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I can't drive (my Moog) 55!         |     The E-Music DIY Archive
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Tony Clark -- clark at andrews.edu     | aupe.phys.andrews.edu/diy_archive
http://aupe.phys.andrews.edu/~clark |     Contributions welcomed!
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