Teensy MIDI looper

I built a simple MIDI looper with the Teensy 3.2 development board

It's a simple device. It has two MIDI inputs, one serving as a THRU port, mostly for forwarding sync messages to the connected device. The other input port is for connecting the instrument. The output port binds the loop for sending and receiving notes.

The first version soldered to a stripboard. The left and center MIDI connectors are the inputs connected to the Teensy (header pins visible) through an optocoupler circuit

Teensy is the perfect fit for this kind of project, mostly due to its tiny dimensions. It works with the same development setup as Arduino, and virtually all libraries that work with Arduino work with Teensy. It even includes a MIDI library, which came in handy. The code is trivial; the gist is that we read the input tempo, start and stop messages from the THRU port and merge the tempo message with incoming note data. The note data quantizes to the nearest 8th sync message.

Up to date feature list and basic build instructions found from the repo

https://github.com/jjylik/teensy-midi-looper

Comments

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