Musicians and makers interested in building their very own DIY synthesizer may be interested in a new Raspberry Pi project published to the Hackster.io website this month. The custom Raspberry Pi synthesizer has been created by Stephan Bourgeois and features a pressure sensitive polyphonic drum pad, 8 x track looper, 8 x effects chain, synthesizer and MIDI controller all in one compact controller.
Bourgeois has used a Raspberry Pi 4 Model B mini PC for the project and combined it with a Texas Instruments EK-TM4C123GXL TM4C Tiva launchPad available to purchase online for around $17. The synthesizer and MIDI controller is housed in a custom-made wooden box and uses a Texas Instruments Code Composer Studio to carry out the processing.
Raspberry Pi synthesizer and MIDI controller
“The synthesizer is composed of three basic parts. There are two midi control boards based on the TM4C123GXL launchpads and a raspberry pi. One midi control board controls the instrument side of the synthesizer and the other controls the looper portion. The instrument portion is comprised of 12 pressure sensitive keys made from force resistors as well as a few knobs for tuning. The looper board has 8 loop tracks and 8 effects.
The raspberry Pi runs Qsynth which is connected to a pure data patch via JACK. Qsynth is connected to the instrument and generates the sounds, while the pure data patch is connected to the looper board and adds effects. The pure data patch also runs a touch screen drum machine controlled by python scripts. All of this code is tested and working, however, the hardware is untested with the firmware and the synthizer was never fully assembled.”
The DIY Raspberry Pi synthesizer project is still currently in the final stages of construction and is awaiting more funds from Bourgeois to complete. However he has kindly made everything available over on Hackster.io for you to build your very own if desired.
“This repository is a collection of design files for a synthesizer I designed, but I ran out of time and money to finish the project. I would not recommend that anyone attempt to build this synthesizer, although I highly recommend reviewing this code. While the code works on evaluation boards and it is very cool, unfortunately, I made a number of mistakes in the design, but the biggest one was the amount of wiring necessary to build it.
I should have made only one circuit board with surface mount devices. I spent way too much money on quality parts instead of making something economical. Ultimately, I had to give up on the design because the hardware was overly complex and a money pit. Essentially I bit off more than I could chew. However, the code does work very well and so it has educational value worth sharing. This was my first venture into hardware design and I learned alot, mainly that hardware is hard.”
Source : Hackster.io