EN Double Pulse WS Success!

R.Fahl 8brain at spiritone.com
Mon Jun 30 08:58:23 CEST 1997

Tonight I finished testing my latest creation, an Electronotes Double Pulse
Waveform Shaper, from EN #73.

Here's a rundown of how it works:  one set of inputs are for pulse width
control (one manual, one CVable).   This is fed into an inverting opamp
summer that sets a negative threshhold for one comparator and a positive
threshold voltage for another after being fed through an inverting amp. The
other set of inputs to this circuit are for audio.  The circuit calls for a
sine wave input, but any audio signal seems to work.  There's a symmetry
trimmer that I made a front panel control, as it adds more versatility.
This is fed through an inverting summer into the negative inputs of both
comparators.  The ouputs of the comparators are fed each into an input of a
pot, which controls the overall waveshape.  The output is then scaled with
another opamp and that gives you the output.

The idea behind this waveshaper is to create odd harmonic only waveforms.
It does a great job of creating pulse waves from hollow to buzzy, and
sometimes ring mod-ish sounding.  I'm quite happy with it, as it is very
simple to build and it is much more versatile than a typical PWM circuit.


An unexpected demographic and cognitive constellation co-occurs with
synesthesia: females and non-right-handers predominate, the trait is
familial, and memory is superior while math and spatial navigation suffer.
Synesthesia appears to be a left-hemisphere function that is not cortical
in the conventional sense. The hippocampus is critical for its experience.
Five clinical features
comprise its diagnosis. Synesthesia is "abnormal" only in being
statistically rare. It is, in fact, a normal brain process that is
prematurely displayed to consciousness in a minority of individuals.


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