When designing a wind instrument such as a clarinet, it can be useful to be able to predict the playing frequencies. This paper presents an analytical method to deduce these playing frequencies using the input impedance curve. Specifically there are two control parameters that have a significant influence on the playing frequency, the blowing pressure and reed opening. Four effects are known to alter the playing frequency and are examined separately: the flow rate due to the reed motion, the reed dynamics, the inharmonicity of the resonator, and the temperature gradient within the clarinet. The resulting playing frequencies for the first register of a particular professional level clarinet are found using the analytical formulas presented in this paper. The analytical predictions are then compared to numerically simulated results to validate the prediction accuracy. The main conclusion is that in general the playing frequency decreases above the oscillation threshold because of inharmonicity, then increases above the beating reed regime threshold because of the decrease of the flow rate effect.

Some new measurements made of the oscillation of air-driven accordion reeds show that higher transverse modes through the fourth mode are present as well as the first torsional mode. The second and third transverse modes are observable even at low amplitudes of oscillation. All of these have been previously observed in reed organ reeds [Paquette et al., J. Acoust. Soc. Am. 114, 2348 (2003)]. Additionally, for the first time a lateral mode of vibration (transverse vibration perpendicular to the usual first transverse mode) has been observed. For airflow in a given direction, only one of the two reeds mounted in each wind chamber is the primary source of sound production, but the vibration of the secondary reed has also been studied. The amplitudes of higher-frequency modes relative to the fundamental are observed to be higher in the secondary reed than in the primary reed. Finite element calculations of the reed modes have been made, and the calculated mode frequencies and node locations were used to verify mode identification. [Work partially supported by National Science Foundation REU Grant No. PHY-0354058.]

The input impedance measurement can provide the resonance frequencies of an instrument and is a standard method used by wind instrument makers in designing modifications. For a complete design, it is necessary to know the playing frequencies themselves, which depend on several control parameters, such as the blowing pressure and reed opening and the input impedance. Using the values of these parameters, we can determine the playing frequencies. This research will analytically deduce these frequencies from the different control parameters and from the input impedance curve. Four effects are known to influence the playing frequency and are examined separately: the flow rate due to the reed motion, the reed dynamics, the inharmonicity of the resonator, and the temperature gradient in the clarinet. The results for a particular clarinet are given and compared to numerically simulated playing frequencies. Experimental methods are also presented and discussed.

To improve understanding of super heavy-lift rocket acoustics, this letter documents initial findings from noise measurements during liftoff of the Space Launch System's Artemis-I mission. Overall sound pressure levels, waveform characteristics, and spectra are described at distances ranging from 1.5 to 5.2 km. Significant results include: (a) the solid rocket boosters' ignition overpressure is particularly intense in the direction of the pad flame trench exit; (b) post-liftoff maximum overall levels range from 127 to 136 dB, greater than pre-launch predictions; and (c) the average maximum one-third-octave spectral peak occurred at 20 Hz, causing significant deviation between flat and A-weighted levels.

This work defines transition times between articulated notes for reed instruments such as clarinets and bass clarinets. To determine these transition times, analysis of measurements of musician mouthpiece pressure, measured using sensor-equipped mouthpieces made especially for the clarinet and bass clarinet is required. The transition time (△T) can then be compared in different musical contexts (dynamics, tempos, etc.), playing regimes, and between various players. The data collection method and metric definition will be described, and results from different playing situations will be offered.