Title: Acoustic Criteria and Procedures for Adjusting Tone and Response in Woodwinds
Abstract: Bore and tone hole proportions of three clarinet types (Oehler, Albert, and Boehm) were obtained for instruments including those of outstanding players here and abroad. Resonance curves were measured for many. Measured resonances closely match those calculated via bore, tone hole, and bundary-layer perturbations plus reed dynamics. Acoustical features of these clarinets are correlated with musical strengths and weaknesses. Acoustical “diagnosis” can be based on playing experiments. Systematic reaming and lacquering of an instrument is possible, to give qualities preferred by the player. Low-register pitch stability, full tone, and solid attack requires tuning of the second-mode resonance (with the reed in action) to within 5 cents of the third harmonic of the played frequency. Higher harmonics including those of clarion register frequencies mostly lie in the “open-holes passband,” where the resonance frequencies are pseudorandom. It is sufficient to tune one of these resonances to some harmonic of the played note. Elimination of all sharp corners reduces damping at low sound levels, and gradualizes the onset of turbulence at high levels, giving an increase in dynamic range. Related procedures are known for flute and recorder; bassoons and oboes respond similarly.