Prynth

The Prynth framework uses the Raspberry Pi (RPi) for sound synthesis and the Teensy microcontroller for sensor signal acquisition. The Teensy communicates with the RPi through an add-on board, which in turn connects to up to 10 multiplexer boards for a total 80 analog sensor connections (pots, resistors or switches). It also includes connections for digital sensors through I2C and SPI buses.

With the Prynth framework, the RPi boots into a system that automatically runs a web service with a full code editor for the SuperCollider programing language.

For more information please visit the Prynth website.

Installation

Prepare the OS

• Flash the latest Raspbian Lite image (https://www.raspberrypi.org/software/operating-systems/#raspberry-pi-os-32-bit) to your microSD card.
• Mount the card on your computer and create an file named ssh located at the root of the boot folder. In Linux:
  touch ssh
• If you want connect straight to your WiFi, you can also create a wpa_supplicant.conf file on the same booh folder. The wpa_supplicant.conf file should contain:

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=GB
network={
    ssid="your_real_wifi_ssid"
    scan_ssid=1
    psk="your_real_password"
    key_mgmt=WPA-PSK
}

• Boot Raspberry Pi.

Expand filesystem

• SSH to Raspberry Pi and run the Raspbian configuration program.
  • sudo raspi-config
• Expand filesystem: "7 Advanced Options" > "A1 Expand Filesystem".
• Reboot.

Upgrade and install additional libraries

• SSH to Raspberry Pi.

• Update libraries.

  • sudo apt-get update
  • sudo apt-get upgrade
  • sudo apt-get dist-upgrade

• Install additional libraries required for Jack and SuperCollider.

• sudo apt-get install libsamplerate0-dev libsndfile1-dev libasound2-dev libavahi-client-dev libreadline-dev libfftw3-dev libudev-dev libncurses5-dev cmake git

• Reboot.

Compile and install Jack

• git clone git://github.com/jackaudio/jack2 --depth 1
• cd jack2
• ./waf configure --alsa --libdir=/usr/lib/arm-linux-gnueabihf/
• ./waf build
• sudo ./waf install
• sudo ldconfig
• cd .. && rm -rf jack2

Set limits.conf

• sudo sh -c "echo @audio - memlock 256000 >> /etc/security/limits.conf"
• sudo sh -c "echo @audio - rtprio 75 >> /etc/security/limits.conf"
• exit # and ssh in again to make the limits.conf settings work

Compile and install Supercollider

• git clone --recurse-submodules https://github.com/supercollider/supercollider.git
• cd supercollider
• mkdir build && cd build
• cmake -DCMAKE_BUILD_TYPE=Release -DSUPERNOVA=OFF -DSC_ED=OFF -DSC_EL=OFF -DSC_VIM=ON -DNATIVE=ON -DSC_IDE=OFF -DNO_X11=ON -DSC_QT=OFF ..
• sudo cmake --build . --config Release --target install
• sudo ldconfig

Test Jack and SuperCollider

• Connect your soundcard (USB or I2S)
• Run Jack with sound device 1 (-dhw:1)
  • jackd -P75 -dalsa -dhw:1 -p1024 -n3 -s -r44100 &
• Run SuperCollider
  • sclang
• Inside the sclang shell, boot the server and play an event. You should hear a sound.
  • s.boot
  • (dur:3).play
• Quit the server and exit sclang
  • s.quit
  • 0.exit

Setup UART for Prynth boards and enable overclocking

• SSH to Raspberry Pi.
• Run Raspiconfig:
  • sudo raspi-config
• Disable shell over serial and enable hardware port:
  • 5 Interfacing Options > P6 Serial
  • "Would you like a login shell to be accessible over serial?" > No
  • "Would you like the serial port hardware to be enabled?" > Yes
• Reboot.
• SSH to Raspberry Pi.
• Additional boot settings (disable Bluetooth and enable overclocking)
  • sudo sh -c "echo dtoverlay=pi3-disable-bt >> /boot/config.txt"

Clone prynth in the pi home folder

• cd ~
• git clone https://github.com/prynth/prynth.git

Install Node.js, liblo and WiringPi

• sudo apt-get install nodejs liblo7 liblo-dev wiringpi

Recompile the pbridge application

• gcc -o /home/pi/prynth/pbridge/pbridge /home/pi/prynth/pbridge/src/pbridge.c -lwiringPi -llo

Enable Prynth at startup

• Launch crontab
  • crontab -e
• Choose your preferred text editor (nano is easier)
• Add the following line at the end of the file:
  • @reboot sudo nodejs /home/pi/prynth/server/bin/www
• Reboot.

Notes

For more information please refer to the Prynth documentation. Prynth is also distributed as a ready-to-use image file hosted on the Downloads section.