AMYboard is a compact DIY music synthesizer board designed for integration into custom music projects or installation as a Eurorack-compatible 10HP module. The board is powered by an ESP32-S3 module and runs the open-source AMY synthesizer engine, which supports multiple synthesis techniques including virtual analog, FM, wavetable, and sample playback.

The system is built around the ESP32-S3-WROOM-1 module, which provides a dual-core Xtensa LX7 processor with integrated Wi-Fi and Bluetooth connectivity. The module runs the AMY synthesizer engine and manages audio processing, MIDI handling, and communication with external peripherals.

ESP32-S3 block diagram

AMYboard includes ten pre-installed 3.5 mm jacks supporting stereo audio input and output, two control voltage (CV) channels, MIDI input and output, and stereo S/PDIF digital audio. The analog channels can operate at either 1 Vpp line level or 10 Vpp modular level, selectable via onboard DIP switches for compatibility with Eurorack systems.

AMYboard bottom view

A microSD card slot provides storage for samples, patches, and programs. The board also exposes an I²C connector intended for peripherals such as knobs, rotary encoders, or OLED displays for building custom front-panel interfaces.

When connected to a host computer via USB, AMYboard appears as both a USB MIDI device and a serial interface, allowing patch transfer, file management, debugging output, and interactive access to a MicroPython prompt.

AMYboard online application

AMYboard runs the AMY synthesizer engine, a lightweight fixed-point music synthesis library written in C and designed for embedded systems. The engine supports multiple synthesis techniques including virtual analog (Juno-6 style), operator-based FM synthesis similar to the DX7, PCM sample playback, wavetable oscillators, Karplus-Strong string synthesis, and additive partial synthesis.

The system supports multiple oscillators with envelope generators and modulation routing for parameters such as amplitude, pitch, filter cutoff, PWM duty cycle, and stereo panning, along with global effects including filters, chorus, echo, reverb, and a three-band EQ.

Tulip Creative Computer

Patches can be created using an online editor that provides a graphical interface for configuring oscillators, envelopes, filters, and effects before sending them directly to the board. Developers can also control the synthesizer programmatically through Python, C, or Arduino environments using AMY’s event API or compact “wire message” commands.

AMYboard top view

The library also runs on platforms beyond ESP32 including Raspberry Pi, RP2040, and Teensy boards, and includes built-in MIDI handling with note management, controller support, and polyphonic voice management.

AMYboard can also be connected to the Tulip Creative Computer via an I²C interface, allowing the Tulip system to control the synthesizer engine and expand overall polyphony. The Tulip Creative Computer is an ESP32-S3-based platform with a 7-inch touchscreen designed for music, coding, and digital art projects. When paired together, Tulip can act as a controller and development environment while AMYboard handles additional sound generation tasks.

Further Information

The AMYboard is priced at $29.90 and is available through the Makerfabs website.