
The trombone is a musical instrument in the brass family. As with all brass instruments, sound is produced when the player's vibrating lips (embouchure) cause the air column inside the instrument to vibrate. Unlike most other brass instruments, which have valves that, when pressed, alter the pitch of the instrument, trombones instead have a telescoping slide mechanism that varies the length of the instrument to change the pitch. However, many modern trombone models also have a valve attachment which lowers the pitch of the instrument. Variants such as the valve trombone and superbone have three valves similar to those on the trumpet. The word "trombone" derives from Italian Tromba (trumpet) and -one (a suffix meaning "large"), so the name means "large trumpet". The trombone has a predominantly cylindrical bore like its valved counterpart, the baritone, in contrast to its conical valved counterparts: the cornet, the euphonium, and the French horn. The most frequently encountered trombones are the tenor trombone and bass trombone. The most common variants, the tenor and bass, are treated as non-transposing instruments pitched in B♭, an octave below the B♭ trumpet and an octave above the pedal B♭ tuba. The once common E♭ alto trombone became less widely used as improvements in technique extended the upper range of the tenor, but it is now resurging due to its lighter sonority which is appreciated in many classical and early romantic works.