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Musical instruments are said to have a personality, which we notice in the sound that they produce. The oscillation mechanism inside woodwinds is commonly studied, but the transmission from internal waveforms to radiated sound is often overlooked, although it is musically essential. It is influenced by the geometry of their resonators which are acoustical waveguides with frequency dependent behavior due in part to the lattice of open toneholes. For this acoustically periodic medium, wave propagation theory predicts that waves are evanescent in low frequency and propagate into the lattice above the cutoff frequency. These phenomena are generally assumed to impact the external sound perceived by the instrumentalist and the audience, however, a quantitative link has never been demonstrated. Here we show that the lattice shapes the radiated sound by inducing a reinforced frequency band in the envelope of the spectrum near the cutoff of the lattice. This is a direct result of the size and spacing between toneholes, independent of the generating sound source and musician, which we show using external measurements and simulations in playing conditions. As with the clarinet, the amplitude of the even harmonics increases with frequency until they match odd harmonics at the reinforced spectrum region.

The tonehole lattice cutoff frequency is a well-known feature of woodwind instruments. However, most analytic studies of the cutoff have focused on cylindrical instruments due to their relative geometric simplicity. Here, the tonehole lattice cutoff frequency of conical instruments such as the saxophone is studied analytically, using a generalization of the framework developed for cylindrical resonators. First, a definition of local cutoff of a conical tonehole lattice is derived and used to design “acoustically regular” resonators with determinate cutoff frequencies. The study is then expanded to an acoustically irregular lattice: a saxophone resonator, of known input impedance and geometry. Because the lattices of real instruments are acoustically irregular, different methods of analysis are developed. These methods, derived from either acoustic (input impedance) or geometric (tonehole geometry) measurements, are used to determine the tonehole lattice cutoff frequency of conical resonators. Each method provides a slightly different estimation of the tonehole lattice cutoff for each fingering, and the range of cutoffs across the first register is interpreted as the acoustic irregularity of the lattice. It is shown that, in contrast with many other woodwind instruments, the cutoff frequency of a saxophone decreases significantly from the high to low notes of the first register.