Note: Please allow at least 90 days for all Bach special orders (including special backbores or throats). Sometimes this delay is longer.

Bach special orders are non-cancellable and non-returnable. If paying by credit card, your card will be charged in full at the time you place your order.


The backbore of a mouthpiece bears a certain relationship to the rim, cup shape, and throat; as well as to the bore of the instrument on which the mouthpiece is used.

If the backbore of a mouthpiece is too small, the high register will be stuffy and flat. If the backbore of a mouthpiece is too large, the mouthpiece will not have sufficient resistance and the player's embouchure will soon become exhausted.

Keep in mind! :: The use of the general terms "large" or "small" to describe backbores must be viewed from the standpoint of playing qualities. It is not actually possible to identify backbores by size alone because they also vary in shape and rate of taper. Various combinations of size, shape, and rate of taper make the tone darker or more brilliant, raise or lower the pitch in one or more registers, increase or decrease volume.

Standard Vincent Bach mouthpieces match the playing qualities of the backbore with the design of the other components. The following chart lists standard backbores (by cup) and some others.

  • No letters = No. 10 Backbore
  • A Cup Models = No. 24 Backbore: Bigger, darker, symphonic.
  • B Cup Models = No. 7 Backbore: Dark, Schmitt=style
  • C Cup Models = No. 10 Backbore
  • D Cup Models = No. 76 Backbore
  • E Cup Models = No. 117 Backbore: Favors upper register
  • F Cup Models = No. 76 Backbore
  • V Cup Models = No. 25 Backbore: Big, free-blowing, commercial sound
  • More:
  • No. 3 Backbore: Dark
  • No. 87 Backbore: Big, free-blowing
  • No. 41 Backbore: Bright, more resistant
  • No. 57 Backbore: Lively, good high register

  • This information comes directly from the Bach Mouthpiece Manual. Click Here to download the Bach Mouthpiece Manual in PDF.