Journal of the Acoustical Society of America最新文献

With the growing number of hearing aid users and the increasing frequency of travel to or through high altitudes, it is important to understand how altitude affects hearing aid output. This study employed computational simulations to examine how altitude influences the output sound pressure level (SPL) of hearing aids. Simulations were conducted at four altitudes: 0, 2743, 4572, and 10 668 m. The input level was fixed at 60 dB SPL, and gain and compression ratios were prescribed using the National Acoustic Laboratories Nonlinear version 2 formula for four representative hearing loss profiles. The model incorporated the outer ear transfer function and atmospheric absorption, assuming an open-closed tube (2.5 cm long, 7 mm in diameter). Three conditions were simulated: (1) SPLs incorporating altitude-dependent effects without gain, (2) SPLs with prescribed gain, and (3) SPLs with gain under constant temperature. Results showed that both SPLs and resonant frequencies decreased with altitude. Gain application increased overall output levels but preserved altitude-related trends. When temperature was held constant, SPLs continued to decline with altitude, but resonant frequencies remained unchanged. These findings suggest that hearing aid prescription formulas should include altitude-related correction factors, with careful consideration of temperature effects.

While much is known about the public health impacts of civil aviation noise, only limited research has investigated the consequences of military aviation noise, despite it first being recognized over half a century ago. The present study conducted a social-acoustic survey to quantify levels of annoyance and sleep disturbance associated with military aviation noise among communities surrounding Naval Air Station Whidbey Island, Washington State, USA, which serves as a training facility for EA-18G Growler aircraft. We conducted a social-acoustic survey of 663 respondents residing in households across a representative range of military aviation noise exposure levels. We report evidence that perceived exposure to military aviation noise is consistent with modeled annual sound levels across the study region and that noise exposure is positively associated with annoyance and sleep disturbance. We also found that reported annoyance is strongly influenced by active or past service in the U.S. Armed Forces and by expressed attitudes toward military operations. Aviation noise disrupted several routine household activities and triggered different coping strategies in affected communities. By highlighting the implications for human well-being of military aviation noise, this research raises questions about the appropriateness of conventional community noise metrics and mitigation approaches for military aircraft noise.

Binaural audio rendering aims to reconstruct virtual sound images at a listener's ears using headphones or loudspeakers. While headphones can deliver stereo sound separately to each ear, loudspeakers-based binaural audio systems suffer from intrinsic crosstalk, which necessitates crosstalk cancellation (CTC) as a preprocessing technique. Traditional two-channel CTC methods experience performance degradation near ill-conditioned frequencies that are determined by physical system configuration. The optimal source distribution approach overcomes this problem by varying the loudspeaker pair's positions with frequency; however, its application is constrained by the requirement for a large number of loudspeakers. As an alternative approach, this paper proposes an optimal control point distribution (OCPD) method that minimizes the condition number of the transfer matrix by dynamically adjusting control point positions instead of the loudspeaker positions. By selecting appropriate control point locations, the proposed OCPD method effectively mitigates the performance deterioration of traditional two-channel loudspeaker systems at the ill-conditioned frequencies without increasing the number of loudspeakers. Theoretical analysis and simulation results demonstrate that the proposed OCPD method outperforms conventional two-channel CTC systems and, using only two loudspeakers, achieves performance comparable to the discrete optimal source distribution method with five loudspeaker pairs. Experiments conducted in an anechoic chamber validate the theoretical findings and further confirm the effectiveness of the proposed approach.

This study investigated the effects of hearing history on consonant perception scores and confusion patterns in early implanted youth (i.e., child-implanted) and post-lingually implanted adults (i.e., adult-implanted), as well as in participants with normal hearing (NH) who listened to spectrally degraded (vocoded) stimuli. Vocoded consonant perception improved with chronological age in children with NH. For the cochlear implant (CI) users, more auditory experience and shorter durations of deafness were associated with better consonant perception scores, especially in child-implanted listeners. Individuals in the child-implanted group also made significantly more errors in identifying the voiceless fricative, /θ/, than did adult-implanted listeners. Individual differences in phoneme error patterns could inform personalized intervention strategies, and child-implanted listeners might derive particular benefit from interventions that improve access to formant transitions or high-frequency energy. Moreover, while CI experience and early implantation benefit many CI users of all ages, delayed intervention may be more detrimental to the speech perception outcomes of prelingually deafened than post-lingually implanted individuals.

In deep water, a near-bottom vector sensor vertical line array (VSVLA) enables three-dimensional (3-D) passive localization of submerged sources. For a shallow source, localization is typically performed in two steps: azimuth and range estimation using 2-D spatial spectrum estimation (2DSSE), and depth estimation by matching the frequency-domain interference period. However, in multitarget scenarios, the limited spatial resolution of the VSVLA can easily cause missed detections, while multiple threshold detections encounter a severe measurement-to-track association (MTA) problem. To address these challenges, this work adopts a track-before-detect (TBD) framework to avoid the explicit MTA process. The proposed algorithm jointly scans the intensity over the azimuth-range-depth grid using a pre-generated interference-matched kernel function and directly inputs it into TBD as the measurement, effectively mitigating missed detections caused by 2DSSE bright spot overlap. Building on the incorporation of multiple auxiliary particle filter as the tracker, adaptive weight filtering and Rao-Blackwellization strategies are further employed to improve convergence speed and reduce state dimensionality, respectively. The proposed algorithm demonstrates high robustness even under low signal-to-noise ratio conditions and environmental fluctuations. Its localization performance is validated through simulations across multiple complex deep-water scenarios, as well as a towed-source experiment.

Ecological momentary assessment (EMA) is frequently utilized to evaluate hearing programs (HPs) in real life, either by indirect comparison (i.e., rating one program in each study period) or by direct comparison (i.e., switching between HPs in a survey and rating the difference). To compare these methods, a randomized crossover design was implemented with 30 participants and three hearing programs differing in gain and noise reduction features. Data collection spanned 15 days, capturing participants' ratings of sound quality, hearing aid satisfaction, and speech understanding. For programs differing in gain, the direct method showed the highest contrast across the three evaluated attributes. For programs differing in noise reduction features, only the direct method showed a difference in speech understanding. The direct comparison method sampled fewer situations in which using the phone might be inconvenient (e.g., conversations and driving) and was also perceived as more burdensome. Overall, representativeness detected differences between HPs, and participant burden varied between methods, suggesting that the choice of approach is highly context dependent (i.e., whether the focus is immediate perceptual differences, long-term effects, or sampling specific real-life environments). The findings of this study are converted into a set of recommendations for designing an EMA study.

This study extends the theoretical framework of diffuseness estimation to practical microphone arrays with different spatial configurations. Building upon the covariance-based model, we formulate a velocity-only covariance framework that enables consistent diffuseness evaluation across heterogeneous array geometries without requiring mode whitening or spherical-harmonic decomposition. Three types of arrays-the A-format, rigid-sphere, and a newly proposed tight-frame array-are modeled and compared through both simulation and measurement experiments. The results demonstrate that the proposed tight-frame configuration achieves isotropic sampling and reproduces diffuseness characteristics equivalent to those of higher-order spherical arrays, while maintaining a compact physical structure. We also examine the accuracy of acoustic-intensity detection within the same framework. The findings bridge theoretical diffuseness analysis and practical implementations, contributing to the design of robust sound-field measurement systems.

This study investigates the differences in sound emissions of multi-rotor unmanned aerial systems (UAS) between hover and cruise. We therefore conducted onboard acoustic measurements on two different UAS types, each equipped with multiple propeller configurations. The recorded data allowed for a detailed comparison of noise emissions at fixed emission angles, focusing on both traditional acoustic metrics and psychoacoustic parameters. The results reveal notable differences between hover and cruise, with certain configurations exhibiting a sudden increase in sound emission levels of up to 4 dB above specific cruise speeds. While some UAS/propeller combinations showed a linear relationship between cruise speed and sound emission levels, others experienced abrupt level increases beyond a critical velocity of 2-4 m/s, along with changes in loudness and roughness. These variations were not directly correlated with rotor speed changes, indicating that aerodynamic transitions, such as shifts in blade-wake/blade-vortex interactions, strongly influence sound generation. Spectral analyses support the occurrence of an aerodynamic regime change between hover and cruise, with the effect saturating at higher cruise speeds. Consequently, noise and auralization models, but also evaluations on low-noise propellers that are based on measurements at hover state only may yield substantial inaccuracies when extrapolated to cruise state.

Existing methods for reconstructing oceanic three-dimensional sound speed fields (3D SSFs) often exhibit limited accuracy, primarily due to inadequate utilization of global correlations. To address this limitation, this work formulates the 3D SSF as a third-order tensor and introduces a low-rank tensor modeling framework termed the fully connected tensor network (FCTN) model. This model effectively captures the inherent global low-rank properties of the SSF. To further exploit local spatial smoothness, we incorporate factor-based Tikhonov regularization into the FCTN framework, thereby yielding the fully connected tensor network-Tikhonov regulation (FCTN-T) model. For efficient model optimization, we develop an algorithm based on proximal alternating minimization (PAM), integrated with an acceleration strategy to enhance its computational performance. Extensive numerical experiments demonstrate that the proposed FCTN-T method outperforms state-of-the-art approaches in terms of both reconstruction accuracy and computational speed, providing higher-fidelity approximations of the ground-truth SSF and marking a significant advancement in oceanic SSF reconstruction.

Marine acoustic techniques are crucial for exploring and developing the ocean. However, the underwater acoustic (UWA) hyperbolic frequency modulation (HFM) signal suffers from a low signal-to-noise ratio (SNR) in complex environments. Traditional denoising methods rely heavily on prior knowledge and perform poorly in non-Gaussian noise. While neural networks offer an alternative, their computational cost limits underwater applications. In this study, we propose a lightweight time-frequency gated fusion network (LTFG-Net) for long-range UWA signal denoising. First, to overcome scarce data, a dataset is built by transmitting HFM signals through a simulated channel and adding α-stable noise. Second, we design a lightweight denoising network with dual-branch parallel processing in the time-frequency domain. Moreover, by combining pre-training and transfer learning, a two-stage training strategy is proposed to quickly adapt to specific marine environments with limited measured data. Finally, simulation and sea experiments demonstrate the superiority of the proposed scheme. Specifically, numerical results show that LTFG-Net improves the Generalized SNR (GNR) from 0 dB to an average of 43.13 dB, with the correlation coefficient increasing from 0.1928 to 0.8954. In long-range sea trials, LTFG-Net boosts the GNR from 4.56 dB to 38.65 dB and the correlation coefficient from 0.3542 to 0.9122, with only 0.23 M parameters.