Trombone, brass wind instrument with a cylindrical bore, a cup-shaped mouthpiece, and a slide mechanism. Except for its thicker metal and narrower bell, which yielded a softer, mellower tone, the early trombone was basically identical to the modern one. It was a favored instrument in church and chamber music. With its slide closed, a B-flat tenor trombone produces the third B-flat below middle C as its fundamental or pedal note and also the notes in the harmonic series of that B-flat (like a bugle or unvalved trumpet). The slide is successively opened through six more positions, giving a lower harmonic series each time. The range extends from the second E below middle C to the B-flat above middle C, plus four pedal notes (B-flat, A, A-flat, G; the remaining pedal notes, down to low E, are difficult to produce). Orchestral music also uses a bass trombone in F (usually supplied by a double tenor/bass trombone in B-flat/F, which has a valve to switch in extra B-flat bass tubing).
