Rafaele Andrade is a composer and instrument builder working at the intersection of experimental music, live coding, and interactive technology. Her practice centres on the relationship between performer and audience, and on finding ways to make that relationship active rather than passive.

 

Improvising You takes this literally. During the performance, volunteers from the audience wear sensor kits that measure their heart rate and brainwave activity. That biological data flows in real time into Rafaele's setup, where it shapes the music she plays on KNURL, a custom instrument of her own design. This way, the audience is not just watching the show but they participate in it.

 

 

 

 

Through the open call from Open Culture Tech, Rafaele was matched with Superposition, a design-tech studio specialised in creative coding and interactive systems. The first months were spent defining the boundaries of the collaboration: what Superposition would build, what it needed to do, and where the technology should stay out of the way. The decision was made early that the visuals should support Rafaele and KNURL and should not compete with them for attention.

 

Rather than displaying biological data as clinical information, such as waveforms, graphs or readouts, Superposition designed visuals that suggest a shared state between participants. The goal was to evoke a sense of connection between the people wearing the sensors, rather than to illustrate what their bodies were doing.

 

One small design detail that ended up mattering: each sensor kit includes a colour LED on the palm of the wearer's hand. The colour matches the data stream assigned to that person on the main LED display. Participants can look at their hand and find themselves in the shared image.

 

 

A recurring challenge throughout the build was designing for failure. Wearable sensors in a live environment are unreliable by nature. Data drops out, signals get noisy, readings spike without warning. The system had to look intentional under all of these conditions. The visuals needed to hold up regardless of what the sensors were actually sending.

 

On the hardware side, the team ran into a technical ceiling with the off-the-shelf components. The AD8232 ECG module at the core of each kit is capable of capturing heart rate signals, but brainwave signals are significantly quieter and fell below its detection threshold. Superposition modified the circuit, replacing two capacitors and a resistor to increase gain from 60 to 80 dB,  allowing the same board to capture EEG data as well. The modification is based on research by Matías Rodolfo Pretel et al., published by Elsevier under the CC BY 4.0 license. All components were chosen from affordable, off-the-shelf sources to keep the system accessible for future use and adaptation.

 

In total, eight sensor kits were developed: four for ECG, four for EEG. Each is built around a battery-powered ESP32 in a custom 3D-printed enclosure with an ergonomic smartwatch band. The kits connect over WiFi and send data continuously via OSC.

 

A dedicated PC running custom Node.js scripts receives the raw data, applies filtering, and sends the processed output back over OSC to Rafaele's machine running Ableton Live. Max for Live plugins handle communication on the music side. The same PC drives a 480×96 pixel LED display across five 96×96 pixel panels. Visuals are rendered using custom GL shaders with an 8×8 Bayer matrix dithering algorithm, a technique that turns each pixel fully on or off while still producing smooth animation.

 

 

The work was developed through three iterative performance cycles: at V2_ Lab for the Unstable Media in Rotterdam, Cinetol in Amsterdam, and Rewire Festival in The Hague. Each showing fed back into the next. A significant amount of the music developed in direct response to what happened in the room, the reactions of participants, the behaviour of the sensors, the feedback from collaborators.

 

The latest version of Improvising You, including the premiere of KNURL in its most developed form to date, was performed at Rewire Festival in The Hague. 

 

More on Rafaele Andrade's work at www.rafaele-andrade.com. Photos from Flor Verhulst and Papper pictures