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Single-reed musical instruments, such as the saxophone, generate sound through a complex interplay between the mechanics of the reed and the hydrodynamic and acoustic pressure in the instrument mouthpiece. To understand this complex mechanism, experimental data are lacking. This paper presents full-field, time-resolved measurements of strain and displacement of a vibrating saxophone reed, measured under mimicked realistic playing conditions. It is found that strain along the length axis of the reed is mainly expansive, except in a small zone near the tip where it becomes compressive when the reed touches the front edge of the mouthpiece. At the instant in the vibration phase where the reed touches the mouthpiece, significant bending and compressive strain appear along the direction perpendicular to the reed axis. Strain magnitudes in both directions are similar, with absolute values of 0.1%. Full-field strain maps reveal subtle characteristics which are not revealed by displacement measurements. Bi-axial bending and strain may be an essential component in reed mechanics, which up till now has been fully neglected in modelling.

In single-reed instruments, the mouthpiece and reed have an essential effect on instrument playability, since they largely determine the range of lip force and blowing pressure required to produce notes. This paper quantitatively examines the effect of three different mouthpiece designs (Selmer S80, Concept, and Spirit) on the range of lip force and blowing pressure combinations in which tone can be produced on the alto saxophone for notes ranging from D3 to D5. Average lip force, blowing pressure, loudness, and tuning are investigated as functions of notes and for three different reed strengths. Characteristics such as lip-force/blowing-pressure playability area (total playability area, TPA) and correctly tuned playability area (CTPA) are determined for different reed strengths and note values, and change of tuning as a function of notes is investigated. Apparent differences were observed between mouthpieces of different designs and even between mouthpieces with extremely similar tip openings. The Spirit mouthpiece is louder but requires higher lip force and more adaptation of lip force and of blowing pressure over note ranges. The Concept, with a remarkably similar tip opening and facing length as the S80, allows for a smoother transition between the low and high registers of the instrument and has better tuning stability. The new parameters < TPA > and < CTPA > are introduced as summarizing indicators of mouthpiece characteristics, averaged over note range and reed strength range. Such parameters can be used to define mouthpiece playability objectively and can form important input for parameter-based design improvement or customization.

To investigate the acoustics of reed instruments without the need for a human player, blowing machines are needed, which can generate air pressures up to 8 kPa and flow rates up to 40 liters per minute. Due to reed flexibility and the changing pressure gradient across the reed, the relationship between flow and pressure is highly non-linear. Since the output pressure of ventilators is highly dependent on flow, non-linear pressure regulation is a difficult task that requires a closed-loop approach. Since reed vibration starts suddenly when blowing pressure is gradually increased, an abrupt change in airflow through the instrument is present, resulting in a change in pressure in the artificial mouth. To avoid that, a method is presented to achieve a fast response to abrupt flow changes, which is tested in an existing blowing machine. The enhanced blowing machine exhibits a settling time below 200 ms, which allows for the generation of blowing pressures with linear responses.

In single reed musical instruments, vibrations of the reed, in conjunction with the geometry of the mouthpiece and the acoustic feedback of the instrument, play an essential role in sound generation. Up until now, three-dimensional (3D) reed vibration patterns have only been studied under external acoustic stimulation, or at a single note and lip force. This paper investigates vibration patterns of saxophone reeds under imitated realistic playing conditions. On different notes displacement measurements on the entire optically accessible part of the reed are performed using stroboscopic digital image correlation. These vibration data are decomposed onto the harmonic frequencies of the generated note pitch and into the operational modes. Motion data as a function of time are shown on single points. All points on the reed predominantly move in phase, corresponding to the first flexural mode of the reed. At higher note harmonics very low amplitude higher vibration modes are superimposed on the fundamental mode. Mouthpiece characteristics and lip force influence the vibration patterns. Vibration patterns differ strongly from earlier measurements on free vibrating reeds. Results show that single-point measurements on the tip of the reed can give a good indication of the 3D vibration amplitude, also at higher note pitches.

Reed woodwind instruments pose great challenges in modeling because their functioning is based on a combination of hydrodynamics, acoustics, and mechanics. Reproducible measurements therefore remain crucial for further development of reeds and instrument mouthpieces. We present a method to measure reed behavior and acoustic response under realistic, well-defined playing conditions. A measurement setup based on constant phase stroboscopic digital imaging correlation (DIC) is proposed. A computer-controlled timer delay triggering system combined with high-power LEDs allows one to obtain clear images at different phases of the vibrational period. From these high-quality images, digital image correlation DIC allows one to analyze both displacement and strain over the full visible surface of the reed. The presented technique can also be applied to other nonfrequency-imposed vibrating structures. The method is demonstrated on a saxophone reed, and we show how it can be used to determine playability range of a mouthpiece and vibrational behavior of the reed.

The reed is the primary component in single-reed woodwind instruments to generate the sound. The airflow of the player&rsquo, s mouth is the energy source and the airflow is modulated by the reed. The oscillations of the reed control the airflow. Traditionally, instrument reeds are made out of natural cane (Arundo Donax), but in efforts to overcome variability problems, synthetic reeds have been introduced. Previous investigations mainly focused on natural cane reeds and direct elasticity measurements did not discriminate between elasticity moduli along different directions. In order to obtain the mechanical properties along the direction of the reed fibres and in the orthogonal direction separately, a three-point bending testing setup was developed, which accommodates the small samples that can be cut from an instrument reed. Static moduli of elasticity were acquired in both directions. Much higher ratios between longitudinal and transversal moduli were seen in the natural cane reed as compared to the artificial reeds. Wet natural reeds showed a strong decrease in moduli of elasticity as compared to dry reeds. Elasticity was significantly higher in artificial reeds. The force&ndash, displacement curves of the wet natural reed show hysteresis, whereas the artificial materials did not. In the cane reed, higher energy losses were found in the transversal direction compared to the longitudinal direction