Sv: [sdiy] Digital VCO update

[Richard Wentk]

At 22:05 30/04/2006, Michael Bacich wrote:
>Getting back to your question, "Frequency range?", if you're talking about 
>ten octaves of range, then 0.2 Hz to 200 Hz would probably work for me, 
>and would probably be similar to the kind of range we see on LFO's in most 
>modern synths (Korg Triton, etc.).

I'd lower that an octave or two.

A 200Hz LFO isn't musically useful - you might as well use a VCO instead.

But 0.1Hz or even 0.05Hz modulation is musically useful, especially if it 
can synced to a MIDI clock or a sequencer. You can set up long sweeps that 
last a bar or two.

>>* Output voltage range (+/- 5V, or 0-10V?)

Both.

>>* Waveforms?
>
>I'm a traditionalist, I guess.  Sine, Triangle, Square, Saw Up, Saw 
>Down.  Those are the ones that will be used 90% of the time.  I wouldn't 
>waste time including a half-ass psuedo-random "sample & hold" wave, nor 
>would I include any of those fake "noise" waves.

If you have an ADC you can easily turn your LFO into a S&H too

If you're limited by memory then trad waveforms are the way to go.

If not - assorted shapes can be musically useful too to add unpredictable 
animation.

Richard