[sdiy] Sound samples for Obesifier Waveform Animator are up

[sbernardi at comcast.net]

My guess is that having an "animated sine" output is not going to be different  
enough from the animated triangle to make it worth the additional complexity. 
The animated triangle looks like a series of contiguous line segments that are 
constantly changing slope and length; having sine converters in there would 
just add a bit of curvature to the line segments. It's hard to describe, and I 
don't have any way of making a movie of the scope trace.

For the second idea, you would need to make all the LFO's voltage controlled - 
again more complexity.  And I would think the sound wouldn't be that much 
different than controlling one or two of the stages with an external VCO.
> Thank for the interesting insights Scott.  I'll have to dig up the
> relevant articles and re-read.  A couple of thoughts for ROTO (return of
> the Obesifier):
> 1) Would it be a worthwhile experiment to put CA3080 tri-to-sin converters
> on the tri waveforms, mix these and send to a front panel jack?  Or would
> this not sound much different than low-pass filtering and/or add too much
> complexity?
> 2) What about an additional LFO triangle that is used to modulate the 6
> LFOs?  It could also be overridden via external LFO input.
> 
> George
> 
> sbernardi at comcast.net wrote:
> 
> > The saw animator output is pretty identical to the original MWPA, when
> > the LFO's are set in the subaudio range.  The frequency settings were
> > suggested by Bernie in the Electronotes article; the idea was to spread
> > them so that there was no harmonic relationship between them. Bernie
> > sites an article from EN #40 by Ralph Burans who was trying to come up
> > with frequency spacing for filter banks, and hit upon a spacing of the
> > fifth root of 2.1 which gives no harmonic overlap in a 10 octave range.
> > I just used a table from the EN #87 article for resistor values.
> > Now that I've played with the obesifier for a while, I'd do it a bit
> > different. I'm finding that there is not much perceivable difference
> > having the variable frequency LFO's until you get them up into the audio
> > range; and then the best sounds come when you use a VCO for external
> > animation control that tracks the input VCO.  So if I did the circuit
> > again (Obesifier Jr? The Phat Boy returns?) I would cut it down to six
> > animator stages, get rid of the adjustable LFO's and drive all six
> > stages with fixed frequency LFO's, but bring out panel jacks so that the
> > internal fixed LFO could be overridden by an external VCO for animation
> > modulation on two of the stages.
> > I also found a mistake in the saw to tri converters on two stages; with
> > it fixed the animated tri output is mellower and less like the animated
> > saw output than the samples I have up right now. When I get a chance
> > I'll redo the animated tri sample.
> >
> > --
> > Scott Bernardi
> > sbernardi at comcast.net
>