Cup Diameter
In general, smaller instruments, such as trumpets and cornets, utilise smaller diameter cups than their lower-pitched, larger counterparts. The small cup, pressed to the lips restricts them to a smaller free area which can vibrate and, hence, do so at a higher frequency. In part, this is because the lower-pitched sounds of the latge brass, which are generated by the longer wavelengths of the standing wave in the instrument body, can only be generated by the lips when these are sufficiently free to vibrate over a long width. Thus, wider cup diameters allow a larger section of the lips to vibrate than the smaller cups of higher-pitched instruments.
To see how the cup diameter is set using the sliders on this web site, click Setting the Cup Diameter

Cup Depth
In addition to the mouthpieces of larger instruments having a larger diameter cup, they also have a deeper one. This prevents the vibrating lips from hitting the shoulder at the bottom of the mouthpiece but, more importantly creates a body of air between the player’s lips and the narrow opening, the throat, between the mouthpiece cup and the instrument’s backbore. The cavity formed in the cup has its own resonant frequency, that means there are certain frequencies at which the air inside it may resonate much more strongly. These vibrations in the mouthpiece cavity have a profound effect on the performance of the instrument to which they are attached. To see how the cup diameter is set using the sliders on this web site, click Setting the Cup Diameter

Cup Conicity
One group of instruments such as the trumpet have cup-shaped mouthpieces while others such as the French horn have conical mouthpieces. In the mouthpiece.store model, cup-shaped mouthpieces are ones which have a shoulder as shown in the diagram below. A level of conicity may be added to any mouthpiece on this site, either totally, to yield a fully-conical mouthpiece or only partially to give a mixture of cup-shaped and conical characteristics. The area marked as ‘shoulder’ on the diagram below, is not controled directly by the software but appears when particular settings of the cup diameter and depth and throat bite are made. To see how the cup conicity is set using the sliders on this web site, click

The diagram below shows two basic forms of mouthpiece provided by mouthpiece.store.

The difference between the cup-shaped and conical mouthpieces has an important impact on the tone-colour or timbre of the sound an instrument produces. This is because of the way in which particular frequencies are re-inforced or damped out as a result of the shape of the cup. This is just one of the elements which goes towards the generation of the distinctive tone of the various instruments. The trumpet, for instant can have a bright, brassy tone, whereas the French horn is characteristically mellow.