Wide range oscillator

Has anyone made a wide ranging VCO for rack? There are plenty of modules that can switch to an LFO mode for more range, but how about an oscillator that sweeps from ultra low to ultra high frequency? V/oct isn’t really a priority for this type of thing, so no need to worry about the VCV voltage standard for pitch cv. This isn’t the kind of oscillator you’d want to use for precise melodic work anyway, but rather to do things like smoothly transition between rhythmic and melodic temporal states, or perhaps theremin style heterodyning using ultra high frequencies.

The VCV Fundamental VCO and LFO both should be able to do what you want. They do not clip the V/Oct input, so you can scale the voltage to offer a huge range. You can get an extreme range simply amplifying the incoming V/Oct by a factor of 2.

With the VCV VCO at its native 0V = C4, I was able to send in -20V and get an extremely slow rate. If my math is right, that results in one cycle taking longer than 1 hour.

Going in the opposite direction with an LFO, you are limited by the Nyquist frequency. You don’t even need to amplify the FM input to exceed the Nyquist frequency, even with an extreme engine rate. Setting the VCV engine rate to 192 kHz, and the VCV LFO to its max 1024 setting, passing in 6V should take us to 64 kHz. The Nysthi Tunismo measured the output at 66.2 kHz. Not sure if the error is in the LFO or the meter.

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I made a google sheet to do the calculations.

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Thanks, yeah I realised after I posted this that I could just use something like the bogaudio offset to rescale the input. Works fine. I just had a little thought bubble moment there where I was thinking about how in my hardware rack I have a few oscillators that only track v/oct over a few octaves and do that pretty poorly at best. I like the way that these oscillators break my habits. I was also thinking about how much I like the design of those ACL oscillators that have a frequency knob that goes around and around (those still have range switches though). I’m also thinking about how it is strange that we categorise VCOs and LFOs as though they are distinctly different things (of course, they are both just oscillators). I would personally appreciate some module designs that intentionally abandon the “standards” (the only one I can think of is Vult Vultari).

And yes, we’re limited by nyquist at higher frequencies. Didn’t realise we could already get so high using the fundamentals. Cool.

This is exactly the kind of precision I’m not interested in, but thanks for your efforts.