A contrabass trombone is a brass instrument which is the lowest in pitch out of the trombone family. The trombone family is notable for having a slide mechanism for changing notes rather than valves. The pitch can be further lowered on a contrabass trombone with the use of one of two valves which are operated by the thumb. These allow the instrument a low note of Ab0, the A flat found just past the very bass end of a piano. Some contrabass trombones have two slides and older versions have a very long slide that must be operated using a handle.
The appearance of the contrabass trombone has been different throughout history. The instrument is always much larger than a regular trombone, but similar in design. Some contrabass trombones have two slides, stacked one on top of the other, which are both used to alter the note produced by the instrument. Older models used to have a very long slide with a handle to help the player extend it fully. They were so long that they couldn’t be fully extended by a player with his or her mouth on the mouthpiece at the opposite end.
Valves are used on a contrabass trombone to further lower their range. Two valves are included on most contrabass trombones, which are operated with the player’s thumb. These valves open up additional sections of tubing which lower the pitch of the instrument. Either one of the valves or both of them can be opened by the player. Most songs don’t require both valves to be opened.
The lowest note on the contrabass trombone is A flat just lower than the lowest pitch on a piano. This note is referred to as Ab0, which indicates its position on a piano. This note is produced when both valves are opened on the instrument. The lowest pitch produced by the instrument without valves activated is F1. This is lowered to Eb1 with the use of the first valve and to Bb0 when the second is activated.
All trombones are members of the brass family of instruments. These are notable for their brass construction and the method of playing them. Noise is produced on brass instruments by the player buzzing his or her lips into a cup-shaped mouthpiece while breathing out. Most brass instruments are pitched in B flat and have valves to change the note. Trombones like the contrabass trombone change note using a slide mechanism.