Parts of the Mouthpiece
Knowing the components of a mouthpiece will help you know how to get the level of comfort, ease of play, and solid tone that you want. A mouthpiece consists of the rim, cup, throat, and backbore.
The rim and cup are the most vital components of the mouthpiece, forming a bridge between the player and the instrument. The rim is the main point of contact and must be comfortable and seal against the lips while still allowing them to move inside the cup to affect pitch and tone. While important to sound, feel, and performance, the throat and backbore are matched to the cup and rim by the manufacturer and are of less concern. Most players will find that a mouthpiece with a medium cup and rim will suit them quite well.
The rim is the round edge of the mouthpiece that you place your lips against to play your horn, and therefore is one of the most crucial parts to consider. A rim with a fairly flat contour allows nice, even lip pressure for a good air seal and feels very comfortable, but doesn’t give much flexibility. Rounded rim mouthpieces give a lot of flexibility, allowing the lips to move back and forth in the cup, but also require more lip pressure and muscular lips. A player without the air volume and embouchure needed will end up pressing too hard against their lips, cutting off circulation and limiting the flexibility gained from using a rounded rim. In this case, a medium-wide rim with a semi-rounded contour and a slightly sharp inner edge is preferred. This rim will provide sufficient surface for easy lip pressure and also give the player the lip movement needed to cover a wide range.
The cup is the cup-shaped area the player blows into inside the rim. Generally, the larger and deeper the cup the darker the tone and more volume it produces. Large cups also require more control, which can quickly tire the player. As the cup gets smaller and shallower the tone brightens, control and response is improved, and less effort is required. Going too shallow can kill volume and flexibility. In choosing cup depth, keep two things in mind: the pitch of the instrument and the individualities of the player, such as embouchure, lung power, and the lip/teeth formation. When selecting cup diameter, go for the largest diameter you can comfortably use without tiring yourself too quickly. The benefits are a more uniform response across all registers and easier lip control resulting in more flexibility.
The throat is the opening leading out of the cup. Do not expect to see wide variations in throat size or length. The throat’s job is to let you push air from the cup and concentrate it into a stream without too much, or too little, back pressure. A bigger throat will allow you to blow harder and produce more volume but it will also require more air pressure from your lungs and make playing soft passages very difficult. A too-small throat will choke your tone and produce more back pressure than is comfortable. Most manufacturers design the throat to complement the cup and backbore design in order to achieve the best tone and projection.
The backbore is the chamber that transfers your breath to the horn. The backbore must match the overall design of the other components of the mouthpiece with slight alterations possible in order to blow comfortably and provide good intonation. Changes in shape and size can produce a brighter or darker tone, raise or lower volume/projection, and raise or lower pitch. The backbore that has emerged as the preferred choice in all-around performance and tone is not very large or small with a smooth, slightly curved taper from throat to well-rounded, even backbore.
