Mouthpiece (brass)

On brass instruments the mouthpiece is the part of the instrument placed on the player's lips. The mouthpiece is a simple circular opening that leads, via a semi-spherical or conical cavity, to the main body of the instrument.

Mouthpieces vary to suit the tone of the instrument. Lower instruments also have larger mouthpieces, to maximize resonance (see pitch of brass instruments). Also, mouthpieces are selected to suit the embouchure of the player, to produce a certain timbre, or to optimize the instrument for certain playing styles. For example, trumpet and trombone mouthpieces are usually semi-spherical whereas French horn mouthpieces are conical.

The mouthpiece has a large effect on instrument sound. Major effects are due to the shape of the cup, shape of the throat, and the inner rim diameter. In addition, players often choose a mouthpiece that complements their playing styles. In general, brass players who concentrate on the upper range prefer a mouthpiece with a narrow bore, and players who emphasize the lower range prefer a wider bore. The cup depth also heavily influences the tone of the brass instrument. A shallow cup will brighten the sound, which is good for trumpeters doing a solo, while the deep cups darken the sound, which is better for blending in with an orchestra.

Makers commonly construct mouthpieces from one of two types of material, with different costs, properties, and features. Metal mouthpieces can be plated with some other metal. Some of the following assertions, especially those regarding the effect of plating on tone color, are questioned by many players and specialists.

Mouthpieces have traditionally been formed of solid brass. Due to brass often containing lead and being toxic upon contact, brass mouthpieces are usually plated with either gold or silver to protect the player from potential brass poisoning.

Plastic mouthpieces are usually made of Lexan plastic, and are often available in various colors. They are durable and don't dent as do metal mouthpieces. Less expensive than metal mouthpieces, players commonly use them when playing outdoors—particularly marching brass players—because their heat conductivity is far less than in a metal mouthpiece. Players who prefer metal mouthpieces generally believe plastic mouthpieces have an inferior tone quality and feel compared to metal.

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Wikipedia