The latest issue of Make magazine (number 15) is devoted to build-them-yourself, high-tech musical instruments. And the coolest of the bunch is this laser harp, at right, being played by its inventor, tech musician Stephen Hobley.
You coax out the computer-generated sounds by waving your hands to break the light beams and change their lengths.
To build a laser harp, you’ll need to be familiar with and fearless about such things as MIDI (Musical Instrument Digital Interface) technology, circuit boards, photo cells, voltage regulators, and computers. If you’re not a serious music technology geek who’s been tinkering for years in the garage, you’ll need to buy or scare up a significant amount of hardware and software.
Stephen’s article in Make does include a simpler project—a single-beam “laser theremin,” as opposed to the six-beam laser harp. But even that’s still a pretty complex gizmo.
Whether or not you dive into this project, we’re sure you’ll appreciate the sights and sounds of the harp in action. Check out Stephen’s video demo, below.

PROJECT SNAPSHOT
> Topics: Computers, electronics, music, light, sound.
> Location: At home, or in your secret laboratory.
> Cost: $19 for the plans and schematics; order from Stephen Hobley’s Web site. Significant additional cost for parts and equipment.
> Gear: Computer, MIDI utility software, software synthesizer, USB-MIDI interface, soldering equipment, insulated wire, wire cutters and strippers, multimeter, alligator leads, saw, drill, vise and clamps.
> Level of difficulty: Pretty technical.