Sackbut Sackbut A sackbut is a type of trombone from the Renaissance and Baroque eras, characterised by a telescopic slide that is used to vary the length of the tube to change pitch. Unlike the earlier slide trumpet from which it evolved, the sackbut possesses a U-shaped slide, with two parallel sliding tubes, which allows for playing scales in a lower range. Records of the term "trombone" predates the term "sackbut" by two decades, and evidence for the German term "Posaune" is even older. "Sackbut", originally a French term, was used in England until the instrument fell into disuse in the
Sackbut between the bell stay and the bell is thought key to a resonant bell, and thus a better sackbut sound. Original instruments have a hinge joint. Modern copies with a tuning slide in the bell can need more support for operation of the slide, so either an extra stay by the tuning slide is provided or a joint without play in only one axis is employed. The original way to make the slide tubes was to roll a flat piece of metal around a solid cylinder mandrel, and the joining edges soldered together. Modern manufacturers now draw the tubes. They