Organ manual

A manual is a musical keyboard designed to be played with the hands, on an instrument such as a pipe organ, harpsichord, clavichord, electronic organ, or synthesizer. The term "manual" is used with regard to any hand keyboard on these instruments to distinguish it from the pedalboard, which is a keyboard that the organist plays with his or her feet. It is proper to use "manual" rather than "keyboard," then, when referring to the hand keyboards on any instrument that has a pedalboard.

Music written to be played only on the manuals (instead of using the pedals) can be designated by manualiter (first attested in 1511, but particularly common in the 17th and 18th centuries).

Organs and synthesizers can, and usually do, have more than one manual; most home instruments have two manuals, while most larger organs have two or three. Elaborate pipe and theater organs can have four or more manuals. The manuals are set into the organ console (or "keydesk").

The layout of a manual is roughly the same as a piano keyboard, with long, usually ivory or light-colored keys for the natural notes of the Western musical scale, and shorter, usually ebony or dark-colored keys for the five sharps and flats. A typical, full-size organ manual consists of five octaves, or 61 keys. (Piano keyboards, by contrast, normally have 88 keys.) Some smaller electronic organs may have manuals of four octaves or less (49, 44, or even 37 keys). Changes in registration through use of drawknobs, stop tabs, or other mechanisms to control organ stops allow such instruments to achieve an aggregate range well in excess of pianos and other keyboard instruments even with manuals of shorter size.

On smaller electronic organs and synthesizers, the manuals may span fewer octaves, and they may also be offset, with the lower one an octave to the left of the upper one. This arrangement encourages the organist to play the melody line on the upper manual as he plays the harmony line or chords on the lower manual.

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