Dynamic realtime stereo sampler for Eurorack modular synthesizer - STM32H7
Aarebot is a dynamic realtime sampler built as a Eurorack module. At its core is a stereo tape-style engine with a hot-swapping record/playback buffer - this enables to record and play simultaneously. Slicing markers can be added on the fly, and processing through an onboard effects chain.
Samplerate decimation trades fidelity for length. A Schroeder reverb blooms into lush endless space or rings into sharp metallic resonance depending on the XY effect mapping.
More DSP FX and taillred XY mapping is on the way and will turn Aarebot into a IDM LOFI crunch machine.
- Stereo hot-swap record/playback buffer
- Realtime sample slicing with manual slice marker placement
- Hermite interpolation for smooth pitch shifting (±24 semitones)
- V/Oct pitch tracking (−1.5 V to +5 V)
- Samplerate decimation for extended recording time and lo-fi texture
- Nonlinear exciter
- Schroeder reverb with prime-length delay lines and scalable room size
| Interface | Function |
|---|---|
| Pot 1 | Base pitch (±24 semitones) |
| Pot 2 | Envelope attack |
| Pot 3 | Envelope decay / release |
| Pot 4 | Recording decimation |
| V/Oct | Pitch CV input |
| CV 2 | XY effect plane - X axis |
| CV 3 | XY effect plane - Y axis |
| Gate 1 | Record |
| Gate 2 | Play |
| Gate 3 | (unassigned) |
| Gate 4 | Set slice marker |
- STM32H7 MCU
- Custom I2C audio codec driver
- 4x WS2812 RGB LEDs for visual feedback
- ADC calibration with 2-point and piecewise CV calibration
- Full KiCad schematic and PCB design
- SPICE simulations for analog input/output stages
├── firmware/ STM32CubeMX project and C source
| ├── Aware Main firmware implementation
| └── Src CubeMX generated src files
├── hardware/
│ ├── aware01_h7_rev2_0/ KiCad schematic and PCB
│ └── simulation/ SPICE simulations for analog stages
└── docs/
└── images/
Requires arm-none-eabi-gcc, cmake, and ninja.
# Configure
cmake -S . -B build/Debug \
-G Ninja \
-DCMAKE_TOOLCHAIN_FILE=./cmake/gcc-arm-none-eabi.cmake
# Build
cmake --build build/DebugDesigned in KiCad. The hardware directory contains the full schematic, PCB layout, and SPICE simulations for the analog input and output conditioning stages.