Air Columns And Toneholes- Principles For Wind Instrument Design |link|

For cylindrical bores (clarinet), the register hole (speaker key) is placed at a specific node of the third harmonic to force the 12th. For conical bores, the octave key is placed to disrupt the fundamental mode without killing the first overtone.

Several examples of wind instrument design illustrate the principles discussed above: For cylindrical bores (clarinet), the register hole (speaker

If a pad sits too high above the tonehole when closed, the trapped air volume allows some sound to leak through, damping high harmonics and making the note stuffy. Conversely, a , closed at one end (e

Conversely, a , closed at one end (e.g., by the player’s lips or a reed) and open at the other, supports a node (minimum displacement) at the closed end and an antinode at the open end. This geometry produces a harmonic series containing only odd integer multiples of the fundamental: f, 3f, 5f, 7f ... The clarinet, overblowing at the twelfth rather than the octave, classically demonstrates this principle. closed at one end (e.g.