psuedo-random timing generator

[Rob]

For all the ppl who believe that perhaps much of the feel of the 303
sequencer is due to the random timing slag of the uPD, I had a real
revelation, and, although I presented my idea in this forum earlier, I
thought that perhaps no one understood my reasoning behind it..

Ok, my first idea was to take the clock circuit of the uPD and AND it
with a variable frequency.. this would induce random errors at random
points as the timing signal would be delayed occasionally. The clock
signal itself could only be delayed from 0 to n, n being 1/2 the
wavelength variable frequency. This would be interesting. But it has a
problem: most uPD are somewhat specific with how wide the pulse is...So,
what happens if the pulse cut off too early by the variable frequency? I
wouldnt think this too much of a problem, but.. Since I really only care
about delaying the onset of a note, I guess I could use a scheme whereby
once the clock circuit is hi, it is enabled until it sees the neg edge
of the clock... I guess just reset on the negative edge from the
original clock circuit would do it..So thats possible.

So, my other idea was to use this variable frequency to randomize the
timing of the gate, DAC latch, and accent line of the 303 clone..The way
I had it set up, by varying the frequency of the randomizer, you could
achieve a maximum of a few uS to a max of 10mS of delay. Of course, for
any given step, the randomizer might not have any delay, or a big delay,
depending on the max delay amount setting.

But, another idea I had is, what if you could allow it to randomize the
timing only on certain steps? Say, using a mux, allow it to randomize
only steps 1, 5, 7, and 9. Would this be more useful or musical? Really,
in a way, one could program in theyre own psuedorandom groove and limit
the occurence to a particular step. I guess, with a little extra
circuitry and by hijacking the 555 I was using to generate the
frequency, I could add a switch to put the 555 into one-shot mode and
allow ppl to use the frequency pot for a delay pot...
wow!

Things are getting interesting!

Rob