The
Hammond organ is an
electric organ invented by
Laurens Hammond in 1934 and manufactured by the Hammond Organ Company. While the Hammond organ was originally sold to
churches as a lower-cost alternative to the wind-driven
pipe organ, in the 1960s and 1970s it became a standard keyboard instrument for
jazz (specifically, the
organ trio),
blues,
rock, church and
gospel music.
The original Hammond organ used
additive synthesis of
waveforms from
harmonic series made by mechanical
tonewheels that rotate in front of electromagnetic pickups. The component waveform ratios are mixed by sliding drawbars mounted above the two keyboards. Although many different models of Hammond organs were produced, the Hammond B-3 organ is most well known. In the late 1960s and throughout the 1970s the distinctive sound of the B-3 organ (often played through a
Leslie speaker) was widely used in blues,
progressive rock bands and
blues-rock groups. The last electromechanical Hammond organ came off the assembly line in the mid-1970s.