(1) A piece of fir or other resonant wood placed behind the strings of a piano for the purpose of increasing the power of the sounds.
(2) In an organ, the sound board is that chamber of air into which the feet of the pipes are placed.
(3) A wood screen placed behind a pulpit for the purpose of reflecting the preacher's voice; or over it, to prevent the sound from ascending into a lantern-tower, or a dome. (Stainer, John; Barrett, W.A.; A Dictionary of Musical Terms; Novello, Ewer and Co., London, pre-1900)
A sound board, or soundboard, is the surface of a string instrument that the strings vibrate against, usually via some sort of bridge. The resonant properties of the sound board and the interior space/volume of the instrument greatly increase loudness over the string alone. (wikipedia)
Sound Box
A chamber for dampening sound emission to an ambient level. (Thomas, Ralph H.; Ultrasonics in Packaging and Plastics Fabrication; 1974, Cahners Publishing Company, Inc., 89 Franklin Street, Boston, Mass. 02110)
See Also