Heartbeat midi controller
This heartbeat controlled MIDI project design by Recotana who is the meber on MAKE Flickr pool ,This project consist of  microcontroller PIC12F675, IR photo sensor,opamp,very small midi controller detect a heartbeat, and MIDI send.it very cool! Interesting choice in sound patch for the demo video - emphasizes that man/machine contrast. Now we just need one more clip documenting a heart-pounding treadmill recording session.
   Heartbeat midi controller
This is full detail on Heartbeat midi controller website
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