First of all for those who don’t know, the monome is a music controller which is used to generate sound effects, is has a lot of push buttons which have different color back lights to generate a visual effect to. DJ’s VJ’s use the commercial version, but there are also available DIY kits, open source open hardware designs, the most simple is to use the Arduino with the monome shield, but you can build your custom shield or entire system.
The basic functions are, use a large keyboard matrix, with back lit buttons and based on the sequence which the user pushes the keyboard generate a MIDI output which is interpreted by a mixer or synthethizer.
The sound and visual effects can be customized if you build your own monome, most of the parts can be bought from Sparkfun, including the pcb’s, although there are open source projects, the programming part is not for beginners and you need some external MIDI interpreter which can be expensive.
Monome with Arduino: [Link]
here is what the author of the project writes about it: This project uses an SX48 microcontroller at 75 MHz as an 8-channel frequency-synthesis music player with three instruments (selectable per channel): square wave, triangle wave, sinwave. Each channel can play an different pitch. The desired pitch is used to lookup how far to step along the sample waveform each 1/44100 second tick, thereby playing back the waveform at that pitch’s frequency.
The waveform is 1024 bytes long (only one-quarter is stored). The music data comes from stripping a bare-bones set of events from a MIDI file: NOTE ON, NOTE OFF, TEMPO, PROGRAM CHANGE. Each active channel contributes a 13-bit, signed, 2’s complement sample to a 16-bit accumulator. The accumulator is then DC-biased to an unsigned format and then the most-significant 12-bits are serially written to a 12-bit MCP4922 dual serial DAC. (I only use one channel).
The output sample frequency is approximately 44.1 KHz. The actual value is (75,000,000 / 8) / 212. The output of the DAC is fed to one side of a 10K trimpot, the other end being tied to ground and the wiper being the input to the positive input of an LM386 audio amplifier…
SX48 mini MIDI music player: [Via] – [Link]