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Subject: RE: In a moment of clarity...

From: The Old Crow <oldcrow@...
Date: 1999-11-01

On Mon, 1 Nov 1999, Dave Bradley wrote:

> 1. Don't sawtooth waves sound more like strings than pulse? Any way to get
> around that?

A uC sawtooth generator is a bit more involved than a pulse generator,
but once the basic phase accumulator is working it is a relatively simple
matter to add up the requested saw datapoints and generate the notes. Of
course, this means...

> 2. You have 8 voice polyphony generated by the processor, using an external
> filter, so how do you do the enveloping/VCA for each note separately? Do you
> have separate output jacks for each polyphonic 'voice'?

...to generate individual saw outputs would needs an octal S/H to store
the waveform data points. A single output could be summed up inside the
uC. Enveloping would be up to other modules. The "string head" would
provide gates/triggers. I think Maxim makes an octal voltage-output
DAC...maybe someone here works for Maxim and can provide a few samples. ;)

(Enveloping ∗could∗ be done in the uC code, but I think it would be
better for other modules to deal with this. I just want to provide the
tones and triggers).

--Crow

/∗∗/