Tonewheel

A tonewheel is a relatively primitive apparatus for generating electronic musical notes. The tonewheel assembly consists of a synchronous AC motor and an associated gearbox that drives a series of rotating disks. Each disk contains a set of bumps that generate a specific frequency through a corresponding pickup assembly, consisting of a magnet and coil. The frequency depends on the speed of rotation of the disk and the number of bumps. A single fundamental frequency can be combined with one or more harmonics to produce complex sounds. A tonewheel was used in the Teleharmonium and in the original Hammond organs.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

In cases such as in a Hammond organ, you will get tonewheel leakage. This is because of the large amount of tonewheels in the organ - the pickups overhear other tonewheels than the exact tonewheel it is meant for. This cause the organ to produce chromatic harmonics. Mostly, this is bad, but in some genres this has become an important part of the hammond sound. On some digital simulations of Hammond organs you have and option to set the amount of tonewheel leakage.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Note: In music, a note is either a unit of fixed pitch that has been given a name, or the graphic representation of that pitch in a notation system, and sometimes its duration, or a specific instance of either, so one can speak of "the second note of Happy Birthday" for example. The general and specific m...

AC motor: An AC motor is an electric motor that is driven by an alternating current. It consists of two basic parts, an outside stationary stator having coils supplied with alternating current to produce a rotating magnetic field, and an inside rotor attached to the output shaft that is given a torque by the...

Gearbox: Gearbox can mean several things:...