[sdiy] Hard Sync on DCOs

[Tom Wiltshire]

Fredrik Carlqvist did it nicely on the Minod Vorga, I reckon.

He repurposed the Pulse Width control to turn it into a "Shape" or "Timbre" control. With the waveshape switched to square, it's a pulse width control and modulation produces PWM. With it switched to ramp, it's a sync slave freq control and modulation produces a sync bend. The zero setting gives a straight ramp wave and turning it up increases the slave freq. Seems pretty straightforward. It doesn't even need a separate 'sync' switch.

Tom.


On 10 Nov 2011, at 02:08, Andrew Simper wrote:

> I agree with Tom, I think it would be a very cool feature, but I can
> also undertand why manufacturers didn't use it. On the front panel it
> would need at least one knob a clicked "off" position at the bottom,
> and then increase in pitch of the vco above that. This is what I do in
> a synth I did called Strobe, there is a single "sync" knob. Also
> typical sync sounds need need modulation of the VCO pitch from lfo or
> env, so that would be more front panel real estate gone. The 10%
> tracking problem I don't think is a big deal since the main audible
> pitch is still coming from the master reset clock of the sync, the 10%
> would just be a change in timbre between each voice, which would sound
> cool. Since there would be no way to increase the pitch of the VCO
> without sync then it shouldn't matter too much.
> 
> Andy
> --
> cytomic - sound music software
>