Modulating an Eurorack modular setup from Ableton Live

A modular synthesizer is definitely a useful tool to experiment with when it comes to sound design and generative, complex intersections. Modular systems are by definition capable of virtually achieving every kind of possible result, going from standalone live rigs all the way to tiny effect boxes, however it’s up to the user to decide which modules to collect and how to put them all together. For those like me, who work with softwares and operate in the box (inside the computer) most of the time, efficiently integrating any external gear into their workflow is crucial and that’s where a hybrid system configuration comes in handy.

Here we’re specifically going to take a look at how to use Modulators 21 (K-Devices suite of advanced Max For Live modulators)  to completely drive an Eurorack synthesizer in order to create a generative, ambient patch filled with complex textures.

Before even getting started on the topic, let’s clear out the basics of how the signal travels from the computer to the modular.
There are essentially two protocolos to dialogue with the system: CV and MIDI.

  • CV (Control Voltage) is what allows modules to get interconnected and modulate each other. As the name suggests, it’s essentially pure voltage, tuned to serve different purposes. Its analog nature implies that signals are continuous and have no discrepancy between their infinite possible values, hence granting an higher resolution of control and fine tuning. While, technically speaking, it’s not possible to generate pure continuous analog signals from a digital source, thanks to nowadays sampling rate resolutions the difference is in fact inaudible. In order to be able to send out CV from the computer, however, we need to use a so-called DC coupled audio interface, which allows inaudible frequencies to travel untouched to the external world (any DC coupled audio output can be used to control any modular synth). These interfaces can also be used to send modulation signals from the modular back into the software;
  • MIDI is the well known standard used to transmit data from all different instruments, both in the box and hardware, with a control system based on a scale 128 integer values for each parameter on each channel. Its low-resolution nature makes it less suitable for modulation signals (while, on the other hand, it’s great to play notes), although modulating external parameters via MIDI is definitely doable and its drawbacks are hardly noticeable in most applications. On top of that, MIDI to CV converters (control via MIDI, output Control Voltages) are way cheaper than DC coupled audio interfaces.


In my setup, I’m using the ES-8, a module-shaped DC coupled interface from Expert Sleepers. However, based on the aforementioned premise, it’s safe to say that converting digital data to CV is only needed when looking for a higher modulation resolution, while MIDI is completely fine in most use cases. Modulators 21 includes tools to convert in both formats, called Voltage and MIDI respectively. Since I’m using CV modulation signals, I’m going to instantiate Voltage for each modulation I’m willing to send out to the modular.

Now, let’s take a closer look at my modulation setup in the box. Modulators 21 is a suite of Max For Live devices, therefore I’m running them inside Ableton Live. I’m using LFOH! and LFOO (both advanced and versatile LFOs with complex waveshaping capabilities), along with Voltage of course.

  • I’m planning to use LFOH! to drive a sequencer in my modular, so I’m going to set its waveform to Square (which is the best suitable to control parameters expecting triggers or gates, such as clock inputs of sequencers). I’m then going to set the first Voltage as its modulation target, set it to Trig and set its output to be one of the ES-8 unused outputs. After that, I’m adjusting LFOH!’s Squeeze and Swing in order to create some irregular pulses to make the sequencer jump to the next note at an irregular pattern (recurring at each wave’s cycle). Since I want the patch to evolve slowly, I’m going to set LFOH!’s Time on 1/1nd and set a (quite) slow BPM in my Live project.
  • LFOO, on the other hand, is going to be used to control attenuations and actual modulations on certain modules. Since I’m planning to use all of LFOO’s modulation targets, I’m going to set up 3 Voltage instances, connect each to different waveform outputs and route them out to ES-8 unused outputs. This time, since all of the signals are planned to be used to modulate something, I’m going to leave all of the Voltage instances set on CV. Playing around with their respective parameters, I’m able to create complex shapes for the first two waveforms. In the third one, however, I’m going to make use of the Modulo operator and crank the waveform’s amplitude up while using the Wrap mode, in order to create those hyper fast modulation movements that are peculiar to LFOO. I’m going to set LFOO’s Time even slower than LFOH! at 4/1nd and play around with each signal’s Min and Max parameters to properly adjust (or simply invert) their range. Using LFOO is perfect for creating complex modulation signals that are connected and always move consistently

That’s it for the Modulators 21 setup. Moving onto a quick view of the modular setup, here’s a list of the modules used and how they’re connected:

  • Doboz Prizma is the sequencer receiving triggers from the first LFOH!. Its playback mode is set to Pendulum, meaning the sequence bounces back and forth without playing back the first and last notes twice. Its output is set to send pitch data to Mutable Instruments Plaits;
  • Mutable Instruments Plaits is the main sound source of the patch. It receives pitch data from the Prizma and has its Timbre parameter modulated by LFOO’s second signal. Its Harmonics parameter is also modulated by Falistri’s oscillator;
  • Frap Tools Falistri is used as a modulation source for Plaits’ Harmonics parameter. Its second oscillator’s bipolar output goes into an attenuator module to properly set its range. However, its waveshape falling time is also getting modulated by LFOO’s first signal, causing the overall frequency itself to fluctuate in speed;
  • Joranalgue Filter 8 is filtering the Plaits’ output and has its Cutoff frequency modulated by LFOO’s third modulation signal.

The rest of the patch is just some routing between the modular and the computer in order to create a send/return chain with the other effect modules in the case and have them recorded onto a separate track in the DAW for further processing.

Despite being primarily a software user, I love modular synthesizers and the physical approach they offer to sound design and experimental music. I feel working with this kind of hybrid setup to inspire my creativity and foster research while retaining the technicality which I like to put in when working with the computer. Modular is more of a mindset than just gears.

We are curious to learn more about unconventional modular setups and we have a dedicated thread on our Discord server dedicated to discuss workflow and ideas. How do you use external gears? What do you think about hybrid setups like this one? Feel free to stop by and share it with our community!

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