Corwin Point Is an ESP32-Based Synthesizer Freeform Circuit Sculpture
Built by Erik Brandal, this work of art follows along to the algorithmically-generated music with light pipes and a real-time FFT display.
Inspiration for corwin point
Synthesizers are incredible musical instruments with a nearly infinite number of ways to modify what sounds are output. Typically, they work by generating a series of waves with oscillators that are then modified by filters, mixed with other waveforms, and/or run through instruments such as a keyboard to alter the note(s). So when thinking about generative synthesis, Erik Brandal, the creator of corwin point, had the idea to incorporate renewable sequencers as the main factor when generating music. In simple terms, there is a pair of sequencers that are driven forward by an algorithm, and each step causes a sound to be produced accordingly.
Sculpture design
The structure of corwin point is divided into five main portions, with each one containing some part of the overall circuit. The base motherboard houses digital components, including the ESP32, drivers for the 18 LEDs, and a couple of digital-to-analog converters (DACs), which take the digital waveforms and translate them into analog ones. In the center sit the middle plate and user interface, both of which contain analog components used for generating and modifying the sound profile. To the side is a speaker enclosure with an amplifier, speaker, and Seeedstudio Wio Terminal. Last of all is the tower at the back that holds the free-form delay circuitry in place.
Generating sound
The entire project is focused around the sequencer, whose job it is to set the melody of the music. A randomized algorithm runs on the ESP32, and based on the values generated, will advance the sequence and create an output on one of the DACs. This voltage is then fed into AS33xx-series integrated circuits that use their internal oscillators to generate analog waveforms.
Making adjustments
Beyond this simple analog waveform, users are able to set their own parameters using one of six total potentiometers mounted onto the UI panel near the front. They can set the amplitude envelope, cutoff level, and resonance frequency for both voices, while also leaving open the possibility to change their function in the future. Three buttons to the side are responsible for resetting the algorithm, toggling the delay on or off, and entering into manual mode for tighter control.
Special features
After the music has been created, it is sent to a single ECC82 vacuum tube amplifier before being split. One output is directed towards the delay circuit, while the other goes into the aforementioned Seeedstudio Wio Terminal for FFT analysis and spectral display on its built-in screen. Each of the 18 lightpipes mimic the amplitude for one of the two voices in differing colors, while two sets of white LEDs at the base step through the sequence.
To see and hear corwin point in action, you can watch Brandal's video here on YouTube or read his project write-up.
