Hammond organ
In 1929 Laurens Hammond established his company for the manufacture of electronic instruments. He went on to produce the Hammond organ, which was based on the principles of the Telharmonium, along with other developments including early reverberation units. The Hammond organ is an electromechanical instrument, as it used both mechanical elements and electronic parts. A Hammond organ used spinning metal tonewheels to produce different sounds. A magnetic pickup similar in design to the pickups in an electric guitar is used to transmit the pitches in the tonewheels to an amplifier and speaker enclosure. While the Hammond organ was designed to be a lower-cost alternative to a pipe organ for church music, musicians soon discovered that the Hammond was an excellent instrument for blues and jazz; indeed, an entire genre of music developed built around this instrument, known as the organ trio (typically Hammond organ, drums, and a third instrument, either saxophone or guitar).