How Does an Electric Piano Work?

About Electric Pianos

The electric piano or keyboard has become an essential element of many rock bands, jazz groups and experimental music ensembles. Electric pianos may come in many shapes and designs and generally fall into one of four categories for producing sound: the plucked reed, the struck reed, the struck wire (sometimes called the struck tuning-fork) and the struck string. All electric pianos are equipped with a pickup that allows the sound to be amplified.

Making Sound

An electric Wurlizter piano

In plucked reed pianos, a plastic hook plucks a metal reed. The struck reed design works much the same way, but instead of the reed being plucked by a hook, it is placed over a metal panel and is hit by a hammer similar to an acoustic piano hammer, causing both the reed and panel to vibrate. Struck-wire mechanisms include the traditional hammer as well, but instead of hitting normal piano wire, they strike a wire connected to a long metal sounding bar, allowing the sound to be carried for a longer period, like the sustain pedal on an acoustic piano. Finally, the struck string is the type of electric piano most like an acoustic piano. The hammers hit strings just like on an acoustic piano.

Transmitting Sound

After the reed or string has been struck or plucked, the sound is carried to a pickup. On the plucked reed electric piano, the reed vibrates, and the sound waves that come from the reed are carried to a pickup located next to the reed. For struck reeds, the pickup is also located near the end of the reed and amplifies the sound of the reed. For struck wire electric pianos, the pickup is located near the metal bar that is connected to the wires Struck string pianos have pickups located along the underside of the piano's bridge or the frame.

Projecting Sound

The pickups all send the sound signals to internal or external speakers, projecting the amplified sound of the piano to the audience. Depending on the model of electric piano used and how it is played (with a light touch or more heavily, or with the sustain pedal), it can sound like anything from a regular piano to a marimba or more exotic instrument. Well-known songs using the electric piano include The Doors' "Riders on the Storm," The Beatles' "I Am the Walrus," and The Kingsmen's "Louie Louie."