Sackbut

The sackbut is a trombone from the Renaissance and Baroque eras, i.e., a musical instrument in the brass family similar to the trumpet except characterised by a telescopic slide with which the player varies the length of the tube to change pitches, thus allowing them to obtain chromaticism, as well as easy and accurate doubling of voices. More delicately constructed than their modern counterparts, and featuring a softer, more flexible sound, they attracted a more sizeable repertoire of original chamber and vocal music than many instruments contemporary with them.