Analog, Meet Digital: MOTU Volta Connects the Mac to CV Synths, Effects Graphically

Computers speak digital signal. Analog synths and modulars speak control voltage. (It’s sort of a “men are from Mars, women find these metaphors insulting” kind of situation.)
What if you could bridge the two elegantly and graphically, using a drag-and-drop, modular interface with calibration and control features? MOTU has developed a solution called Volta. It’s a plug-in that turns your audio interface into a control voltage device. It works with all MOTU audio interfaces that have quarter-inch outputs, and MOTU intends to make it work with any 3rd-party audio interface with DC-coupled quarter-inch outs.
In other words, one software plug-in does more than what a similar module would do, more easily, more elegantly, all from your Mac. It makes your computer a powerful tool for analog synths in a way that it hasn’t been before – arguably in a way that even digital synths can’t approximate.
I’m pleased to welcome Matthew Davidson of MOTU in a CDM exclusive on Volta’s launch. He describes in detail what Volta is about, and why MOTU developed it.
All photos courtesy MOTU.
A video demo follows, as well.
What is Volta?
Volta is software; a virtual instrument that turns your audio interface into a voltage control interface. Anything with a control voltage (CV) input can be automated from your DAW with Volta. This includes modulars, analog mono synths and even effects processors like the moogerfoogers.
Volta provides access to the automation system of your DAW through ramps. You can draw in whatever whacky timeline based automation you desire and use this high resolution data to control anything with a CV input. No stair-stepping or zipper noise. You can also route any MIDI controller to control voltages. Volta provides audio-rate rendered software LFOs, step and trigger sequencers.
Each instance of volta supports up to 24 slots of outputs, and you can have as many instances of Volta as your hardware allows. For example, a MOTU PCI-424 system with four 24io interfaces provides 96 channels of output.
Of course, you can also use Volta to send note information. MIDI information goes in, and control voltages go out. All control signals are running at audio rate, and MIDI note playback is pre-buffered. This provides sample accurate timing of your external hardware.
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