Product Overview
Mouthpiece gap is the distance between the tip of the shank in the trumpet receiver and the point where the leadpipe starts. This distance has an effect of the resistance, response, flexibility, spread between octaves, and pitch of specific notes.
The optimal gap depends on the player, cup depth, throat size, backbore length, and characteristics of the horn. There are differences of opinion on the effect of increasing or decreasing the gap, probably because the effect depends on so many variables, and on player preferences.
The optimal gap can vary from zero gap to 1/4 of an inch or more. An "average" gap is close to 1/8 inch. Some players and horns seem to be quite gap sensitive and some are less so. The effect of gap on your playing is best determined by trial and error.
Gap adjustment is one way to fine tune your mouthpiece performance, in addition to backbore size and length.
Wedge Variable Length Backbores allow you to vary backbore length. Wedge VLB Gap Adjusting Shanks allow you to go one step farther by changing the gap of your mouthpiece / horn combination. Keep in mind that each horn may require a different shank to achieve the same gap as another horn, and that the optimal can vary from horn to horn.
Shank Sizes: The standard VLB shank has the same OD as our standard mouthpieces and backbores, which is 0.385 inches. This is the same OD as most other manufacturers, recognizing that there is often a variation of +/- 0.001 inches when one measures actual specimens from any maker.
Sizes range for 1 to 7 and have an outer diameter at the tip from .371 to .391 inches in .003 thousand of an inch increments. Each change is size corresponds to about .06 inches more or less gap.
Our standard .385 shank corresponds to a #5 and is similar to a #5- 5.5 Reeves sleeve.
This set includes a #3, #4, #6 and #7 shank, to increase and decrease the gap by .12 inches (2 X .06 inches per shank) in each direction, for a total adjustment range of .24 inches, or almost 1/4 inch.
The combination of an adjustable backbore length and mouthpiece gap provides the ultimate ability to fine tune the performance of your backbore with a specific horn and cup combination. Individual shanks and sets qualify for our usual 90 day money back guarantee. Shanks purchased as a set must be returned as a set, not as individual parts.
