The tonehole diameter should be roughly 25–35% of the bore diameter for comfortable fingering (recorders), and 40–60% for keyed instruments (flutes, saxophones) to achieve good cutoff frequency.
An air column supports —patterns of pressure nodes (minimum displacement) and antinodes (maximum displacement).
A comprehensive guide to how air columns behave in wind instruments and how toneholes, bore geometry, and keying affect pitch, timbre, intonation, and playability. This guide covers acoustic fundamentals, practical design rules, modeling approaches, tuning strategies, manufacturing considerations, and measurement/testing methods.
: The clarinet acts as a closed pipe, supporting only odd harmonics ( ), which gives it a distinct "hollow" sound.
The thickness of the instrument wall affects the "inertia" of the air in the hole. Thicker walls can make an instrument feel more stable but may slow down the response.
When a tonehole is opened, the standing wave inside the instrument leaks out. This shifts the acoustic open end (the pressure node) near the position of the open hole.
When a musician opens a tonehole along the body of an instrument, the moving air wave inside encounters a sudden drop in acoustic impedance. The air column meets the outside atmosphere sooner than it would at the physical end of the instrument.
These taper from narrow to wide (e.g., saxophone, oboe). They produce a full harmonic series, giving them a richer, "vocal" timbre.
Undercutting involves flaring the internal edges of a tonehole where it meets the main bore. This technique allows makers to fine-tune an instrument without changing the external hole size.
The tonehole diameter should be roughly 25–35% of the bore diameter for comfortable fingering (recorders), and 40–60% for keyed instruments (flutes, saxophones) to achieve good cutoff frequency.
An air column supports —patterns of pressure nodes (minimum displacement) and antinodes (maximum displacement).
A comprehensive guide to how air columns behave in wind instruments and how toneholes, bore geometry, and keying affect pitch, timbre, intonation, and playability. This guide covers acoustic fundamentals, practical design rules, modeling approaches, tuning strategies, manufacturing considerations, and measurement/testing methods. The tonehole diameter should be roughly 25–35% of
: The clarinet acts as a closed pipe, supporting only odd harmonics ( ), which gives it a distinct "hollow" sound.
The thickness of the instrument wall affects the "inertia" of the air in the hole. Thicker walls can make an instrument feel more stable but may slow down the response. Thicker walls can make an instrument feel more
When a tonehole is opened, the standing wave inside the instrument leaks out. This shifts the acoustic open end (the pressure node) near the position of the open hole.
When a musician opens a tonehole along the body of an instrument, the moving air wave inside encounters a sudden drop in acoustic impedance. The air column meets the outside atmosphere sooner than it would at the physical end of the instrument. They produce a full harmonic series
These taper from narrow to wide (e.g., saxophone, oboe). They produce a full harmonic series, giving them a richer, "vocal" timbre.
Undercutting involves flaring the internal edges of a tonehole where it meets the main bore. This technique allows makers to fine-tune an instrument without changing the external hole size.
