Brass instrument the player of a brass instrument has direct control of the prime vibrator (the lips), brass instruments exploit the player's ability to select the harmonic at which the instrument's column of air vibrates. By making the instrument about twice as long as the equivalent woodwind instrument and starting with the second harmonic, players can get a good range of notes simply by varying the tension of their lips (see embouchure). Most brass instruments are fitted with a removable mouthpiece. Different shapes, sizes and styles of mouthpiece may be used to suit different embouchures, or to more easily produce certain tonal
Cornett to be a difficult instrument to play—it requires a lot of practice. It embodies a design that survives today in the Russian Vladimir horn or rozhok. The main tube has only the length of a typical woodwind, but the mouthpiece is of the brass type, relying on a combination of the player's lips and the alteration of the length of the sound column via the opening and closing of the finger holes to alter the pitch of the musical sound. Most modern brass instruments are considerably longer than the cornett, which permits the use of harmonics, the sound being altered