Via Hackster.io: Max Williams’ modular HiFi amplifier uses an Adafruit ItsyBitsy M0 Express running CircuitPython to make great music:
Here is my project to build a HiFi preamplifier. This includes schematics, PCB layouts, CircuitPython code (on GitHub), BoMs, measurements and photos.
Features:
- High performance design with measurements
- Quality components
- Completely digitally Controlled
- Modular design
- All open source
Components
The preamplifier is made up of a number of connected components:
- MDAC attenuator (PCB, code): Controls the volume
- Input selector (PCB, code): Selects the input
- Encoder panel (PCB, code): Holds rotary encoder and LED indicator
- Power Supply 5V (PCB): Power supply for digital components.
- Power Supply +/- 15V (PCB): Power supply for MDAC attenuator op-amp
- Micro controller board (PCB): Holds the micro controller and other connectors
- RCA panel (PCB): For the RCA sockets and connectors
The PCBs and schematics were created in KiCad and the code that runs on the microcontroller is CircuitPython.