Plasmatronics is a company, founded by former Air Force Weapons Laboratory (now Phillips Laboratory) scientist Dr.Alan E. Hill, which produced aplasma speaker design. This was first demonstrated at the 1978 WinterConsumer Electronics Show.
The product used a conventional dynamicloudspeaker with an integratedamplifier for low frequencies. For a tweeter it used aplasma speaker as a near-masslessdriver. Uniquely, to prevent ozone and NOx emissions it sourced helium from a tank in the back of the unit.
While praised for accurate sound reproduction at demonstrations, the system had a number of disadvantages, including high cost and periodic handling of heavy compressedhelium cylinders.