Soundbeam is a music synthesizer control system designed to allow people with physical or developmental disabilities to create music on any instrument operating with MIDI without physical contact by interrupting a stream of ultrasonic pulses. The Soundbeam master or remote sensor sends out an invisible stream of ultrasonic pulses; when the beam is interrupted, echoes bounce back to the master. Soundbeam detects the interruption, measures the length of time required for the pulse to meet the interruption, measures the length of time required for the echo to bounce back, interprets that information in terms of notes and pitches, and sends instructions for playing the notes to the musical instrument. The length of the beam can be adjusted, allowing both minute movements and sweeping gestures to be used. One set of movements in the beam of the Soundbeam Master creates one channel of information to be sent to one instrument. Up to three soundbeam units can be attached to the Soundbeam Master. Each unit can then interpret movement, creating up to four channels of information and allowing music to be created simultaneously on four electronic instruments or on one instrument capable of playing separate but simultaneous note or sound sequences. Ten selectable MIDI programs in three categories are supplied with the Soundbeam. Single Shot modes provide one note per break in the beam. Sustain modes allow chords to be built with successive beam breaks. Re-trigger modes allows movement within the broken beam to trigger adjacent notes. One re-trigger mode allows scales to be programmed via MIDI input, enabling the user to break the beam at various intervals to play pitches melodically without a keyboard controller. Soundbeam Kit A includes one transformer, one remote sensor, one boom stand, all necessary leads, a handbook, and a video. Kit B includes two each of the transformer, remote sensor, and boom stand, as well as all leads, one handbook, and one video. OPTIONS: Single Switch, Switcher 8, Soundbed, Soundbox, amplifier, MIDIMap software, additional manuals and videos, and a directory of Soundbeam users.