Jonathan Bumstead documents on Hackaday.io a unique laser harp build for the 2019 Hackaday Prize.

Laser harps are musical devices with laser beam “strings.” When the beam is blocked, a note is played by the instrument. Usually laser harps have the beams travel vertically in the shape of a fan or vertical lines.

In this project, I built a laser harp with stacked laser beams that propagate horizontally. The beams reflect off mirrors to form square shaped beam paths. Instead of a MIDI output like my previous laser harp, this device has built-in MIDI player so the output is an audio signal. This means the device does not have to be connected to a computer or MIDI player (e.g. keyboard) to play sound. Both built-in speakers and audio output jack are available for playing music.

The project uses an Arduino Mega and an Adafruit Music Maker Shield for  MIDI music synthesis.

I was so happy to discover this shield, because I can now easily produce audio signals from the device without connecting a MIDI player. Check the link for all the info on how to set up this shield. The shield is run in MIDI mode with the audio output being run to audio jack and speakers. A latched push button turns the speakers on and off.

See all the details on hackaday.io.