Groove Transformer

NIME '24. Supplementary Documents.


This website is prepared as an accompaniment to the paper submitted to NIME 2024 conference.

In this website, we have compiled a number of demos, as well as, all the source codes/files used for developing both the Eurorack module as well as the VST/Standalone clone of the module.

Supplementary Material

To access the provided supplementary material for the Eurorack version, please refer to the Eurorack page. In this page, you will find the source code, pcb, and faceplate resources.

To access the provided supplementary material for the VST/Standalone version, please refer to the VST3 page. In this page, you will find the VST3 source code of the software version of the eurorack module.


The following recordings have been prepared by the authors of the paper. Live concert recordings will be uploaded soon as well.

Live Accompaniment in Virtual Eurorack Environment


  • An arpegiating bassline played back using an ableton stock plugin
  • An Arturia Polybrute synthesizer played live.
  • GrooveTransformerreceiving MIDI grooves from both the arpegiated basseline and the live performance on the synthesizer

Drum Synthesis:

  • Cardinal Virtual Eurorack Environment
  • Cardinal receives the generated drums, strips the gats and velocities to trigger the modules
  • Triggers used to activate voices while velocities are used either as VCA gains and/or synthesis parameters.
  • While 9 voices are generated, some voices were grouped together
  • Typical Kick and Snare (with velocity controled VCAs) were used for kick and snares
  • A single FM Operator was used for all hats (closed and open). The decay of the envelop was controlled by the type of trigger
  • For Rides and Toms, two separate Mutable Instrument Plait modules were used.

Eurorack Jams


For the GrooveTransformer’s input groove, it receives a multiple of the Intellijel Metropolix gate and pitch sequence that controls the Acid Technology Chainsaw voice in the Eurorack. In this scenario, we have opted to use the pitch values of each note event to represent the velocity of the input. The pitch and gate voltages are sent from the Eurorack to the GrooveTransformer via an Expert Sleepers ES-9 DC-coupled audio interface and a Cardinal CV to MIDI converter plug-in. Generated drum patterns from the GrooveTransformer are converted to Control Voltage (CV) and sent to the Eurorack via a PolyEnd Poly2 MIDI to CV converter.

Drum Synthesis:

We use 7 voices of the generated patterns (kick, snare, open and closed hi-hat, and lo/mid/hi tom) to trigger 4 voices in the Eurorack:
Kick: Schlappi Engineering Angle Grinder + Make Noise Moddemix VCA + Intellijel Quadrax envelope generator Snare: Intellijel Plonk Open and Closed Hi-Hats: Basimilus Iteritas Alter Lo, Mid, Hi Toms: Akemie’s Taiko

To retain generated dynamics, the kick, hi-hats, and toms are routed to individual channels on a Mutable Instruments Veils. The level of each channel is controlled with the velocity sequence associated with the corresponding voice The Intellijel Plonk has a dedicated velocity input that we utilized rather than routing the signal to Veils

Video 1
Video 2
Video 3
Video 4

Module Videos (Exploring Synthesis)

Hardware 1

Hardware 2

Additional Jams (Audio Only)

All these sessions were done live and haven’t been editted.

1 - Live accompaniment generated based on a live synth performance. Drums synthesized using Microtonic layered with Acoustic drums
2 - Here we play a sequence of chords (MIDI) and also play the synthesizer live. The drum accompaniments are generated using a modular patch and near the end using acoustic drums as well.
3 - Similar to above, however, the generations were played back on a virtual acoustic drum kit.
4 - In this one, we have programmed 4 sequences on the Electron Analog Four synth which are enabled/disabled during the performance. These sequences drive the accompaniment engine while we perform live on a separate synth as well. At times, we don’t feed the groove of the live performance to the system so that the groove is stable and more conditioned on the programmed sequences
5 & 6 - These jams were done entirely in Ableton. However, we live looped many parallel midi sequences and also played live patterns that were fed to the accompaniment generator. All drums were synthesized using an acoustic drum kit