This project shows you how to build a polyrhythmic sequencer and gives some good information on MIDI. Via MagPi:
Back in The MagPi #58 we showed you our Hexome simulator, running on a mobile device and controlling a sequence. It used concentric rings of trigger positions, starting with a ring of six with each subsequent ring having six more trigger positions. Now we take that basic idea, run with it, fall over, pick up the pieces, and assemble it into a universal polyrhythmic sequencer.
This article was written by Mike Cook and appears in The MagPi #61.
The basic concepts are the same, but this project gives us nearly unlimited flexibility. Each ring generates only one note, and those notes can be changed by mapping. However, almost everything else has changed. There are up to six rings in the sequence: each ring can have a maximum of 32 trigger positions, and can be individually muted. The big change is that each ring can have its own individual sound and volume, courtesy of MIDI.
MIDI stands for Musical Interface for Digital Instruments. It is a very old standard, but still as popular as ever. MIDI is a serial interface that sends messages between musical devices, which include instruments (like a keyboard), and sound modules that generate an audio signal. Some devices can combine the two categories in one device – the most popular being sound-generating keyboards.
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