Circuit bending the Kaossilator?

kaoskid

Greetings,

I'm interested in hijacking the system clock in the Korg Kaossillator Dynamic Phrase synthesizer. Getlofi.com offers the LTC 1799 Precision Clock Kit -$15 USD – LTC 1799 Kit LTC Module, 250K Potentiometer, Kynar Wire, Knob, Switch, Trim Resistors, for $15.

But this seems too hard to control in a musical instrument, so I would like to use a Prop to generate the 1 to 33 MHz signal required. Perhaps it could be useful as a sequencer. Can the Prop generate this signal and vary it rapidly? What would the minimum settling time of the PLL look like? How do I buffer the 33 MHz Prop signal to interface with a 4.5 Volt system?

Thank you for any and all ideas. This concept could be useful for other "circuit bent" musical devices...

Phil Pilgrim (PhiPi)

What you propose is theoretically possible. But the Propeller counter NCO and PLL outputs exhibit phase jitter which will likely produce audible artifacts. The LTC1799 is an analog device which, unlike the Prop, may exhibit slow frequency drift; but there should not be any phase jitter.

-Phil

kaoskid

OK, then how about a digital potentiometer to control the LTC 1799? Maybe low phase noise and jitter could be achieved with a fast (enough) settling time....

Phil Pilgrim (PhiPi)

A digital pot would probably work. It depends on whether 64, 128, or 256 steps give you the resolution you need. Also, I nearly forgot that Chip came up with a way to dither the Prop counters to reduce the audible jitter artifacts in another project. It might work for you as well. You can find the reference to it and code in this thread.

-Phil