swell box

American  

noun

1. a chamber containing a set of pipes in a pipe organ or of reeds in a reed organ, and having movable slats or shutters that can be opened or closed to increase or diminish tonal volume.

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Etymology

Origin of swell box

First recorded in 1795–1805

Example Sentences

This portion of the instrument stands in a cement swell box, its tone being thrown through the arch and into the chancel by means of reflectors.

From The Recent Revolution in Organ Building Being an Account of Modern Developments by Miller, George Laing

The invention of the swell box by Jordan in 1713; 2.

From The Recent Revolution in Organ Building Being an Account of Modern Developments by Miller, George Laing

The “back organ” is usually covered by a swell box, containing louvres or shutters similar to a Venetian blind, and divided into fortes corresponding with the bass and treble division of the registers.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 8 "Haller, Albrecht" to "Harmonium" by Various