Search results for "Loudspeaker"
showing 7 items of 7 documents
Enhancing the sound absorption of small-scale 3D printed acoustic metamaterials based on Helmholtz resonators
2018
Acoustic metamaterials have recently become of interest for their ability to attenuate sound by breaking the mass-density law. In this paper, acoustic metamaterials based on Helmholtz resonators and capable of attenuating sound up to 30 dB are fabricated for sound absorption applications in the small scale. The proposed metamaterials are subwavelength at a factor of $\lambda /12$ with respect to the lateral dimension of the units. The directional response due to the position of the acoustic source on the sound attenuation provided by the metamaterial is investigated by controlling the location of a loudspeaker with a robot arm. To enhance and broaden the absorption bands, structural modific…
Single-Sided Deafness: Impact of Cochlear Implantation on Speech Perception in Complex Noise and on Auditory Localization Accuracy.
2017
Objective To assess auditory localization accuracy and speech reception threshold (SRT) in complex noise conditions in adult patients with acquired single-sided deafness, after intervention with a cochlear implant (CI) in the deaf ear. Study design Nonrandomized, open, prospective patient series. Setting Tertiary referral university hospital. Patients Eleven patients with late-onset single-sided deafness (SSD) and normal hearing in the unaffected ear, who received a CI. All patients were experienced CI users. Intervention Unilateral cochlear implantation. Main outcome measures Speech perception was tested in a complex multitalker equivalent noise field consisting of multiple sound sources. …
On the feasibility of personal audio systems over a network of distributed loudspeakers
2018
Los sistemas de reproducción de audio personal se ocupan de la creación de zonas sonoras personales dentro de una habitación sin necesidad de utilizar auriculares. Estos sistemas utilizan un conjunto de altavoces y diseñan los filtros necesarios en cada altavoz con el fin de que la señal de audio deseada llegue a cada persona en la sala lo más libre de interferencias posible. Existen propuestas muy interesantes en la literatura que hacen uso de arrays circulares o lineales, pero en este trabajo estudiamos el problema considerando una red de altavoces distribuidos controlados por un conjunto de nodos acústicos, que pueden intercambiar información a través de una red. Enunciamos el modelo de …
A Pedagogical Software for the Analysis of Loudspeaker Systems
2009
In this paper, a pedagogical software for the design and analysis of loudspeaker systems is presented, with emphasis on training students in the interaction between system parameters. Loudspeakers are complex electromechanical system, whose behavior is neither intuitive nor easy to understand by inexperienced students. Although commercial simulation software provides computation of the equations governing loudspeaker systems, they are mainly focused on the final product and are intended for experienced audio engineers. The proposed software was intentionally designed for education and training purposes. This software allows students to investigate loudspeaker systems that involve complex in…
Perception and replication of planar sonic gestures
2012
As tables, boards, and walls become surfaces where interaction can be supported by auditory displays, it becomes important to know how accurately and effectively a spatial gesture can be rendered by means of an array of loudspeakers embedded in the surface. Two experiments were designed and performed to assess: (i) how sequences of sound pulses are perceived as gestures when the pulses are distributed in space and time along a line; (ii) how the timing of pulses affects the perceived and reproduced continuity of sequences; and (iii) how effectively a second parallel row of speakers can extend sonic gestures to a two-dimensional space. Results show that azimuthal trajectories can be effectiv…
Simultaneous ranging and self-positioning in unsynchronized wireless acoustic sensor networks
2016
Automatic ranging and self-positioning is a very desirable property in wireless acoustic sensor networks, where nodes have at least one microphone and one loudspeaker. However, due to environmental noise, interference, and multipath effects, audio-based ranging is a challenging task. This paper presents a fast ranging and positioning strategy that makes use of the correlation properties of pseudonoise sequences for estimating simultaneously relative time-of-arrivals from multiple acoustic nodes. To this end, a proper test signal design adapted to the acoustic node transducers is proposed. In addition, a novel self-interference reduction method and a peak matching algorithm are introduced, a…
Vertical Line Array (VLA) Beam - Forming Algorithm with constant beam width.
2005
The algorithm proposed is a beam-forming algorithm. Many beam-steering and beam-forming algorithms exist and they are all based on the control of delay times between the signals driving the loudspeakers of the line array; this kind of control produces a variable beam-width depending on steering angle and frequency. In our case beam width doesn't depend on frequency and steering angle because a specific beam forming technique was applied by shading the amplitudes of signals for each element of the array according to the frequency applied. Furthermore a weighting function was utilized for spatial windowing. Spatial windowing allows reduction of secondary lobes without varying the directivity …