Clarinet tuning barrel

A precision-machined telescoping barrel for a clarinet, the short section between the mouthpiece and the upper joint. Adjustable length lets the player fine-tune intonation without swapping out an entire barrel.

Built for a Stanford music + product design class. I play clarinet, and the standard correction for intonation drift (the instrument going flat as the body warms and the air column lengthens) is either to pull the existing barrel out a few millimeters or to keep a longer second barrel in your case. A telescoping barrel collapses both options into one and lets the player make the correction continuously, on the fly.

The construction is two interlocking aluminum sleeves with a precision sliding fit and an o-ring seal to maintain the integrity of the air column. The fit tolerance is the whole game: too loose and the seal leaks past the o-ring, killing the tone; too tight and the player can't slide the barrel mid-piece without breaking embouchure. I machined the sleeves with a few microns of intentional clearance and tuned the o-ring squeeze ratio to land the friction in the right window, enough to hold position when set, light enough to slide under thumb pressure.

Designing for a musician means thinking about the millimeters that affect intonation and the feel of the instrument under the fingers at the same time.