Vincent Bach

The Vincent Bach Mouthpiece Numbering System

The numbering system of PeakTone mouthpieces is based upon that developed by Vincent Bach. This, in the case of trumpet mouthpieces, uses numbers from 1 to 20, size 1 mouthpieces having the widest cup diameters while 20 has the smallest cup diameter.

This is explained in the 1954 Vincent Bach Mouthpiece manual in the following way:


Thus, as the cup deepens with decreasing numerical value, the cup diameter is increased, further increasing the volume of the cup. Some makers increase the diameter of the throat along with other cup dimension increases but, in the case of the Vincent Bach trumpet mouthpieces, this is maintained at 3.66mm.

The number allocated to a Vincent Bach mouthpiece is often accompanied by a letter, such as in 7C. The purpose of these letter designations is described in the 1954 Vincent Bach mouthpiece manual in the following way, the odd mixture of upper and lower-case entries being s direct copy from the original.:

MODELS WITHOUT LETTERS HAVE MEDIUM CUPS for B-Flat instruments. They produce a rich, full, clear Teutonic tone, free of nasal twang with great volume and carrying power. Many of our great solo artists prefer these. They are ideal for symphonic band.

“A” MODELS HAVE A VERY DEEP “A” TRUMPET OR CORNET CUP and emit a mellow, lyric tone, very effective for melody work.

“B” MODELS HAVE B-NATURAL TRUMPET OR CORNET CUPS OF MEDIUM DEPTH (half way between B-Flat and C trumpet cups) and have a livelier tone than the rounded tone of the standard B-Flat cups. They are, therefore, well suited to MARCHING BANDS.

“C” MODELS HAVE MEDIUM-SHALLOW “C” TRUMPET CUPS. They produce a vivid, crisp tone and are preferred by symphony men who alternate between B-Flat, C and D trumpets. They are excellent for all-around work.

“D” MODELS HAVE SHALLOWER “D” TRUMPET CUPS and are ideal for 2D” and “E-Flat” trumpets or cornets. The have a sparkling, brilliant tone, especially in the high register. “Stratosphere” artists in the dance field, who continuously play in the extreme high register, use them to advantage.

“E” MODELS HAVE EXTREMELY SHALLOW “E-FLAT” CUPS for sprano trumpets in high E-Flat, E-flat cornet, or E-flat alto trombone. Also excellent for piccolo trumpets in high “F” or “G”.

“W” MODELS have a wide cushion rim. For soft thick lips.

More recent Vincent Bach documentation refers to F cups which have the shallowest cup size and to V cups which have a conical or vee-shaped cup form. On these latter mouthpieces, cup depth is described by an ‘S’ for shallow or ‘M’ for medium. This documentation also uses the X designator to indicate a large ‘cushion’ rim.

The most-recent documentation also states that mouthpieces with an A, B, C, D, E, F and V form have different backbores describing these as, for example, a No. 10 backbore for an “A” Cup model. As there is no indication what a No. 10 backbore looks like, this is not particularly useful.