Musical instrument, the immediate predecessor of the modern trombone, made of thin, hammered metal, with a shallow, flat mouthpiece and a narrow, nonflaring bell. The instrument produced a soft sound that complemented the harpsichord, voice, viol, lute, recorder, and cornett.
The English name sackbut (along with its French and Spanish cognates) was used from the mid-15th century until the 18th century, when the Italian term trombone came into general use.
The sackbut was made in at least four sizes, from soprano to bass. It probably evolved as a lower-pitched version of the Renaissance slide trumpet, which first appeared at the ducal court of Burgundy in the 15th century. Like the trombone, the sackbut featured a predominantly cylindrical bore, narrower than that of the trombone, and a telescopic slide to alter the pitch by increasing or decreasing the length of the tube. Also like the trombone, the sackbut was constructed in three sections: the mouthpiece; the slide joint, an assembly consisting of two parallel and stationary tubes attached by a crossbar, or stay, and covered by a long, U-shaped sleeve (the telescopic slide tube), itself supported with a stay; and the bell joint, a U-shaped tube terminating at the bell. The mouthpiece was inserted into one end of the slide joint, and the bell joint was inserted into the other. The bell joint could be fitted with crooks to change the pitch, and the slide joint often had a hinged handle attached to the stay that enabled the player to slide it further than the length of the arm. The pitch was lowered as the player extended the slide away from the mouthpiece.
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