Voltage Modular and MIDI Out in Cubase

I’d like to explain how I got Cherry Audio’s Voltage Modular to generate Euclidean patterns for Cubase. The process for it should be generalizable to other DAWs, but since Cubase Pro is my daily driver (as a DAW, I guess) I’m going to focus on it.

Euclidean patterns rely on the idea that percussive hits happen regularly in a sequence. You’d select a number of beats – say, 16, so you’d have a selection of 16th notes – and decide that you want five hits to occur regularly in that measure of 16 notes.

The hits might come on beats 2, 9, 16, 22, and 28 – five hits, with no hit being more than seven 16th notes away from any other. You can also add offsets, so that the hits “slide over” to a more appropriate spot in the groove.

This particular pattern sounds a little odd, but this sort of application is rather common in latin music – and, for that matter, in most Western music. The disco beat, example, uses eighth notes, where the high hat is 8 hits per measure (every beat), and the kick drum is four beats per measure (so “1 and 3”) and the snare is two beats per measure, offset by three (so both “three” notes).

The problem – sorry, “problem” – is not only finding a Euclidean generator, but using one. It’s not difficult, but working out the process wasn’t as clear to me as perhaps it should have been, so I’m recording it so that others don’t have to wonder how to do it for as long as I did.

First, you need something to play the notes – any sound source works, but I chose Groove Agent, as it’s in every version of Cubase as far as I am aware, and it’s simple. I chose the first drum kit sample in the list, which works out to … “29 Min Jupiter.”

That’s not a bad sample set in the first place, but it’s really not extremely relevant; you can choose anything that generates sound.

I then added Voltage Modular as a MIDI instrument. This opens a modular “rack” in software. I wanted to play with three euclidean generators (high hat, kick drum, snare), all driving the Groove Agent kit.

Voltage Modular has two Euclidean generators in its module store: Euclidean Duel and the uQuence Sequencer. Both work. Euclidean Duel is $20, uQuence is $10; I’m choosing uQuence for this because it supports more generators, and for pretty much no other reason.

I also need to convert CV to MIDI; as a modular, Voltage uses CV to control everything, and I want to send MIDI notes (actually note on/off events) to Groove Agent. I want to work with three generators, so I need to add three “CV to MIDI” modules to my rack.

Lastly, I need to send the MIDI notes back to Cubase, so I need to add a “MIDI Out” module. Thankfully, I only need one of these, as I can chain multiple MIDI cables to the input of this module.

Now that I have my modules, I need to connect them.  This is actually very simple; uQuence has a “gate” output for each generator, and all I need to do is connect each gate to a MIDI to CV module. This will generate a MIDI note every time the gate is tripped.

The next question is, of course, which MIDI note; there’s a “transpose” on the CV to MIDI that allows us to choose the note trivially. (There are options here, but we’re doing this the simple way.) It just so happens that the default note is C1 (which maps to the kick drum in “29 Min Jupiter”), so we only need to transpose two of the three CV to MIDI modules: one will be transposed two steps (thus mapping to a snare) and the other will be transposed six (to map to a high hat.)

After we’ve mapped the gate outputs on uQuence to the CV to MIDI modules, we connect each MIDI output to the MIDI input of the MIDI Output module. That leaves one remaining step – we need to tell the MIDI Output module where to send the notes, and in this case we choose “Send to DAW.” 

All told, here’s what Voltage Modular looks like when we’re done building our modules:

As we can see, we selected measures of 32 beats, and the first generator – our “bass drum” will play every fourth 32nd note (thus, eighth notes, right?) our high hat will play seventeen notes every 32 beats, and our snare will play five, with a slight offset.

This still won’t make a sound.

What we need to do NOW is tell Groove Agent to use Voltage Modular as a MIDI source. To do that, we go back to Cubase, and … well, tell it to use Voltage Modular: 

Now, if we “turn on” the Euclidean Generator (by selecting the “on” in the clock controller of uQuence) we’ll start hearing a cacophony of noise from Groove Agent.

There’s still something to work out, unfortunately: how do we get the transport from Cubase to control Voltage Modular? Ideally we’d want the generators to run when the transport in Cubase is running, rather than on their own.

I don’t know how to do this … yet.