[sdiy] a different kind of slide

[media.nai at rcn.com]

>The time constant of the TB303's slide is fixed and constant. It makes
>no difference with the speed of the sequencer. There is no premonition,
>no clever circuitry, its a RC filter, thats all.

Well, it certainly doesn't sound like any other RC filter, even when
sequencing other CV synths.  The MC-202 also uses a D/A converter using a
4050 buffer and R-2R ladder, and also uses 4066 switched RC portamento, but
it sounds nothing like the TB-303, even when sequencing other CV synths.

Nor can I get a TB-303 modified with CV/Gate inputs to sound like its being
driven by its internal sequencer when driven by any other sequencer,
including the voltage output from another TB-303 (programmed without
slides) run through an external lag processor.

>>As you know, the 303 is a bit more complicated.
>
>No its glide circuit is simple.

Then why does the slide output of the uP go to the clock input of the hex
latch??

>What IS different about the TB303's glide implementation is that the
>glide is always enabled for a brief moment before every note whether
>glide is programmed or not. Charge injection spikes into the timing
>capacitor may produce a slight blip in the VCO's pitch, as well as the
>fact that the CV is lagged slightly on every new gate. This may or not
>be audible.

It may be audible, but I do not think that provides a complete explanation.