Tonewheel in the context of "Electronic organ"

The Hammond organ is an electric organ invented by Laurens Hammond and John M. Hanert, first manufactured in 1935. Multiple models have been produced, most of which use sliding drawbars to vary sounds. Until 1975, sound was created from rotating a metal tonewheel near an electromagnetic pickup, and amplifying the electric signal into a speaker cabinet. The organ is commonly used with the Leslie speaker.

Around two million Hammond organs have been manufactured. The organ was originally marketed by the Hammond Organ Company to churches as a lower-cost alternative to the wind-driven pipe organ, or instead of a piano. It quickly became popular with professional jazz musicians in organ trios—small groups centered on the Hammond organ. Jazz club owners found that organ trios were cheaper than hiring a big band. Jimmy Smith's use of the Hammond B-3, with its additional harmonic percussion feature, inspired a generation of organ players, and its use became more widespread in the 1960s and 1970s in genres such as rhythm and blues, rock (especially progressive rock), and reggae.

The Telharmonium (also known as the Dynamophone) was an early electrical organ, developed by Thaddeus Cahill c. 1896 and patented in 1897. The electrical signal from the Telharmonium was transmitted over wires; it was heard on the receiving end by means of "horn" speakers.

Like the later Hammond organ, the Telharmonium used tonewheels to generate musical sounds as electrical signals by additive synthesis. It is considered to be the first electromechanical musical instrument.

A clonewheel organ is an electronic musical instrument that emulates (or "clones") the sound of the electromechanical tonewheel-based organs formerly manufactured by Hammond from the 1930s to the 1970s. Clonewheel organs generate sounds using solid-state circuitry or computer chips, rather than with heavy mechanical tonewheels, making clonewheel organs much lighter-weight and smaller than vintage Hammonds, and easier to transport to live performances and recording sessions.

The phrase "clonewheel" is a play on words in reference to how the original Hammond produces sound through "tonewheels". The first generation of clonewheel organs used synthesizer voices, which were not able to accurately reproduce the Hammond sound. In the 1990s and 2000s, clonewheel organs began using digitally-sampled real Hammond sounds or digital signal processing emulation techniques, which were much better able to capture the nuances of the vintage Hammond sound.