Any of a class of musical instruments made of brass or other metal, including trumpets, bugles, trombones, and horns. The function of a reed is served by the lips, shaped and tensed by the mouthpiece, acting as a valve releasing periodic pulses of pressurized air into the tube. Orchestral brass instruments are derived from signaling instruments that in their natural or valveless form produce a directionally focused range of tones from the harmonic series by overblowing to as high as the 16th harmonic. They are powerful and efficient generators, and produce tones of great depth and resonance.
In the symphony orchestra the brass instruments are the French horn, trumpet, trombone, and tuba. In the brass band (in descending order of pitch) they comprise the cornet, flugelhorn, tenor horn, B-flat baritone, euphonium, trombone, and bombardon (bass tuba).