Mouthpiece (brass) 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
Bit mouthpiece of the mouth with direct pressure, and outward toward the front of the mouth when used with leverage pressure from a bit shank. Action: The single-jointed mouthpiece applies pressure to the tongue, lips, and bars. Due to the V-shape of the bit when the mouthpiece is contracted, it causes a "nutcracker" action, which has a pinching effect on the bars. It also causes the joint of the bit to push into the sensitive roof of the mouth if used harshly. A single-jointed bit with a curved mouthpiece has a more "U" shape tends to decrease the pressure on the roof