The Trombone Click here to listen to the trombone (RealAudio file) The trombone is a brass instrument with a range over two octaves. The two most popular trombones are the tenor and bass, and in a full-scale orchestra one would usually see two of the former and one of the latter. The other members of the trombone family include the alto trombones, found in 19th century scores, treble trombones, found in the music of baroque composers such as Purcell and Bach, and a double bass trombone. The trombone is a non-transposing instrument. Next instrument - the Tuba Previous instrument - the Trombone Back to the Orchestra construction of the trombone Shape and components: Trombones have been made in many sizes, yet the shape hasn't really changed since the early trombones of the 15th century. The instrument features a cup-shaped mouthpiece and a cylindrical bore expanding to a moderate-sized bell. The distinguishing feature of the instrument is the U-shaped slide that plays the same role as valves. The 'telescopic' tubing in the front allows the slide to be moved at will; thus the bore length can be easily altered and different sets of harmonics produced. This enables the trombone to play a full chromatic scale. Mutes are also used Pitch control: The slide has seven different positions, producing a lower set of harmonics as the bore increases in length. Each set is pitched a semitone apart and the range for each position covers over two octaves Sound production: Legato is very difficult as the slide is constantly being moved, therefore the notes need to be articulated. The lips act as the vibrating reed and pitch is improved by good lip control