Journal of the Acoustical Society of America最新文献

Sportiness perception constitutes a critical dimension of electric vehicle driving experience. Despite targeted acoustic enhancement to amplify this perception, the quantifiable and interpretable psychoacoustic correlations between objective sound characteristics and subjective sportiness values remain insufficiently revealed, constraining establishment of sound design frameworks. In this study, 15 interior sound stimuli were recorded in fuel or electric vehicles under varied driving conditions and calibrated to 60 dB(A). Psychoacoustic evaluation (n = 30) was conducted to quantify sportiness perception, and electroencephalography (EEG) recordings (n = 22) were analyzed to assess neural correlations. Results revealed that 4 Hz amplitude-modulated components significantly suppressed 4 Hz oscillations in primary motor cortex (electrode Cz) (r = -0.679, p < 0.01, Pearson), correlated with enhanced sportiness values (r = 0.747, p < 0.01, Pearson). Informed by neural responses, an initial psychoacoustic model incorporating acoustic predictors of loudness and 4/40 Hz modulation power was developed, outperforming the model with conventional sound quality metrics (adjusted R2 = 0.841 vs 0.682). These exploratory findings could advance our understanding of vehicular auditory sportiness perception and provides a psychophysical framework grounded in neural dynamics for optimizing immersive sound design in automotive engineering and virtual reality applications.

In wave field synthesis, the target source is typically assumed to be static. Some previous studies have extended this framework by introducing time-varying driving functions to reproduce moving sources. More recently, a study applied the stationary phase approximation under the assumption that the source frequency or velocity is sufficiently high. However, in real scenarios, object speeds are often slower than those considered in that study and natural sounds tend to have greater spectral energy in the low-frequency range. In such cases, the stationary phase approximation may result in substantial errors. To address this, we propose a driving function that incorporates a near-field assumption appropriate for low-frequency or slow-moving sources. We further generalize the method by combining it with a previously established approach. MATLAB (The MathWorks, Inc., Natick, MA) simulations reveal that the proposed method reduces reproduction error when the source is either slow-moving or exhibits low frequency. By comparing the proposed method with existing techniques, we show that it serves as a generalization of previous approaches. As such, this study helps bridge the gap between studies on static and moving sources.

A theoretical framework for modelling the acoustic isolation performance of a bubbly curtain consisting of a circular array of bubbly plumes is proposed. The plumes are considered as cylindrical columns with effective acoustic properties deduced from the conventional formulas for a bubbly medium. The rationale for this design is the ability to engage the collective modes of the plumes leading to favorable low frequency performance, defined by a low insertion ratio. Two analytical models have been evaluated. First, the multiple scattering model expressing the results in terms of the scattering amplitude of individual plumes known from the previous studies and, second, the model of an effective boundary condition imposed on the centreline of the array. It is found that the former model performs better over a broad range of parameters. It is shown that the main parameter controlling the system performance is the reflection coefficient of the array, which can be deduced analytically and used to maximize the suppression of a given frequency of an acoustic noise source. As a demonstration of the predictive capability of the framework, the optimal system parameters are derived and then validated with the results of finite element modelling, showing good agreement.

Vibrato in saxophone playing is produced by modulating the jaw force on the reed, creating complex reed-player interactions. This work presents a physics-based sound synthesis of saxophone vibrato, modeling the instrument's acoustics and the acousto-mechanical reed-lip interaction under lip force modulation. The saxophone's acoustic impedance is measured for use in synthesis. The mouthpiece influence is represented by an acoustic model, coupled to the saxophone through numerical simulations performed with the finite element method using open-source tools. The measured impedance is applied as a boundary condition, and viscothermal losses are included. Reed oscillations under acoustic pressure are analyzed with computer vision and high-speed imaging to estimate stiffness, resonance frequency, damping, and rest opening at various lip forces. A time-domain acoustical-mechanical simulation solves a non-linear system, with results compared to recorded vibrato performances. The study identifies parameters driving vibrato production, highlighting the key quantity linking lip force variations to the phenomenon.

The purpose of the current study was to examine speech rhythm in typically developing children throughout the preschool and school-aged years. A better understanding of speech rhythm during childhood and potential differences between the sexes provides insight into the development of speech-language abilities. Fifty-eight participants (29 males/29 females) aged three to nine years were included in the study. Audio recordings of participants' speech production were collected during a narrative task. Envelope-based measures, which conceptualize speech rhythm as periodicity in the acoustic envelope, were computed. Separate general linear models were performed for each of the rhythm measures. Envelope-based measures (e.g., center of envelope power, supra-syllabic band power ratio) indicated that as children aged, their speech contained more high-frequency content and became dominated by syllabic-level rhythms. Findings suggest that both sexes exhibited a similar refinement of speech rhythm as evidenced by increases in envelope-based measures, with speech production developing a more syllabic rhythmic structure during the preschool and school-age years.

Conductive hearing loss typically results from ossicular chain abnormalities, commonly ossicular fixation or separation. While a precise diagnosis is useful for surgeons, distinguishing between fixation and separation before surgery is challenging. In our previous studies, we reported that sweep frequency impedance (SFI) effectively detects such middle-ear pathologies. However, due to the prolonged sound stimuli, SFI exhibited weaker resistance to noise. In this study, we introduce a novel method using short-time stimulation and adaptive noise reduction to improve SFI performance. The method was applied to both healthy individuals and patients, and a support vector machine was employed to evaluate its accuracy in distinguishing fixation and separation in clinical practice. The proposed SFI yielded results consistent with the original SFI meter but significantly shortened the evaluation time to within 200 ms. Classification results indicate that the SFI achieved accuracies of 98% and 83% for detecting ossicular separation and fixation, respectively. In contrast, such accuracies of traditional tympanometry were 70% and 49% for the separation and fixation. Additionally, the study indicates that gentle lullabies can serve as effective acoustic stimuli. These results suggest that our new SFI has potential for middle-ear testing across all age groups, from newborns to the elderly.

Multi-channel parametric array loudspeaker (MCPAL) systems offer enhanced flexibility and promise for generating highly directional audio beams in real-world applications. However, efficient and accurate prediction of their generated sound fields remains a major challenge due to the complex nonlinear behavior and multi-channel signal processing involved. To overcome this obstacle, we propose a k-space approach for modeling arbitrary MCPAL systems arranged on a baffled planar surface. In our method, the linear ultrasound field is first solved using the angular spectrum approach, and the quasilinear audio sound field is subsequently computed efficiently in k-space. By leveraging three-dimensional fast Fourier transforms, our approach not only achieves high computational efficiency but also maintains accuracy without relying on the paraxial approximation. For typical configurations studied, the proposed method demonstrates a speed-up of more than 4 orders of magnitude, compared to the direct integration method. Our proposed approach paved the way for simulating and designing advanced MCPAL systems.

Non-reciprocal systems have been shown to exhibit various interesting wave phenomena, such as the non-Hermitian skin effect, which causes accumulation of modes at boundaries. Recent research on discrete systems showed that this effect can pose a barrier for waves hitting an interface between reciprocal and non-reciprocal systems. Under certain conditions, however, waves can tunnel through this barrier, similar to the tunneling of particles in quantum mechanics. This work proposes and investigates an active acoustic metamaterial design to realize this tunneling phenomenon in the acoustical wave domain. The metamaterial consists of an acoustic waveguide with microphones and loudspeakers embedded in its wall. Starting from a purely discrete non-Hermitian lattice model of the system, a hybrid continuous-discrete acoustic model is derived, resulting in distributed feedback control laws to realize the desired behavior for acoustic waves. The proposed control laws are validated using frequency and time domain finite element method simulations, which include lumped electro-acoustic loudspeaker models. Additionally, an experimental demonstration is performed using a waveguide with embedded active unit cells and a digital implementation of the control laws. In both the simulations and experiments, the tunneling phenomenon is successfully observed.

Distributed acoustic sensing (DAS) with horizontal fibers has recently begun to be utilized for offshore seismic imaging. During a field experiment in the North Sea, using a fiber crossing a gas pipeline, we observed anomalous wave arrivals on a specific range of channels and shot gathers. We analyzed the arrivals and interpret them as shear waves (S-waves) that are generated when the compressional direct waves impinge on the pipeline. The S-waves subsequently propagate through the pipeline and are recorded on the fiber section crossing the pipeline. With an increased usage of the fiber network for seismic acquisition, this P-S converted wave may be observed more often in future acquisitions. Our analysis shows the pipeline acting as a wave guide over several hundred meters for signals generated in the water column. These insights may be useful for DAS-based offshore pipeline monitoring. In addition to the arrivals generated during the active acquisition, we analyzed transient signals occurring at the crossing in the passive data. While their distribution over time correlates with the tides, their generation mechanism remains unclear. No periodic signals that could be attributed to the flow in the pipeline were observed in the vicinity of the crossing.

Ultrasonic backscatter techniques are being developed to detect changes in cancellous bone caused by osteoporosis. Clinical implementation of these techniques may use a hand-held transducer pressed against the body. Variations in transducer angle with respect to the bone surface may cause errors in the backscatter measurements. The goal of this study was to evaluate the sensitivity of backscatter parameters to these errors. Six parameters previously identified as potentially useful for ultrasonic bone assessment were investigated: apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), frequency intercept of apparent backscatter, normalized mean of the backscatter difference, normalized backscatter amplitude ratio, and the backscatter amplitude decay constant. Measurements were performed on specimens prepared from a polymer open cell rigid foam coated with a thin layer of epoxy to simulate cancellous bone with an outer cortex. Data were collected using a 3.5 MHz transducer for angles of incidence ranging from 0° to 30° relative to the specimen surface perpendicular. AIB and FSAB demonstrated the greatest sensitivity to angle-dependent errors. The source of error was identified as reflection and attenuation losses caused by the cortex. A theoretical model was developed and experimentally validated to predict these losses.