[sdiy] Polyphonic issue revisited.

[Byron G. Jacquot]

>> There is also the NCO which can have the best of both worlds (digital and 
>> analog)....but, it also has its very own problems to solve as well.
>
>Can someone explain me what an NCO is?

Numerically Controller Oscillator.

Poke a tuning value into a register, and it sets a combination of integrator
charge time, reset threshold & makeup-gain.  This generates the usual
sawtooth, which can be further waveshaped for square, PWM, tri, etc.  The
Roland Juno synths used this sort of setup.  Fairly easy to control from a
microprocessor, with circuitry that's not too far from a garden variety VCO.

Byron Jacquot