Bore
DEFINITION
The diameter of the tube of a woodwind or brass instrument. The shape of the bore in part dictitates the timbre or tone color of the instrument. A conical bore instrument, in which the bore grows larger throughout, such as the cornet, produces a mellow timbre while a cylindrical bore instrument, such as the trumpet, which has a constant bore until the flare of the bell, produces a brighter, more brilliant timbre.