Biomedical subjects

J M Kates

Publications and source records attributed to J M Kates.

22 records · Page 2Linked to original sources

PubMed1988

Acoustic effects in in-the-ear hearing aid response: results from a computer simulation.

The response of a hearing aid depends on the design of the instrument and on the characteristics of the individual ear. In this paper a computer simulation of an in the ear (ITE) hearing aid is used to determine the effects on the hearing aid response caused by variations in the size of the ear canal, the magnitude of the eardrum impedance, and the vent size and damping. The simulation results indicate that, for an unvented hearing aid, changes in the size of the ear canal or the eardrum impedance shift the average sound pressure level at the eardrum but have relatively small effects on the overall shape of the frequency response. A vented instrument presents a more complicated situation since the vent modifies the low-frequency response in a predictable manner but can have unexpectedly pronounced effects at high frequencies due to the acoustic feedback.

Acoustic Impedance Tests↗

PubMed1988

A computer simulation of hearing aid response and the effects of ear canal size.

The response of a hearing aid is affected by many factors which include the head and outer ear, the microphone, amplifier, and receiver used in the hearing aid, the properties of the ear canal and the eardrum, and acoustic feedback through the vent. This article presents a computer simulation of an in-the-ear (ITE) hearing aid that includes all of the above factors. The simulation predicts the pressure at the eardrum for a frontal free-field sound source. The computer model was then used to determine the effects on the hearing aid response due to variations in the size of the ear canal. The simulation indicates that, for an unvented hearing aid, changes in the size of the ear canal shift the overall sound-pressure level at the eardrum but have only small effects on the shape of the frequency response. The situation is more complicated when a vent is present, however, since changes in the size of the ear canal that cause apparently small perturbations in the acoustic feedback signal may, nonetheless, have large effects on the overall system response.

Computer Simulation↗

PubMed1987

The short-time articulation index.

In this paper we introduce the concept of the short-time articulation index. This is a procedure for calculating a time-varying articulation index from data on a block-by-block basis. The short-time articulation index can be used to give a running measure of the speech intelligibility for an adaptive noise-cancellation system as it converges. We present an algorithm for calculating the short-time articulation index and give some examples of its use.

Acoustics↗

PubMed1985

A central spectrum model for the perception of coloration in filtered Gaussian noise.

In this paper we describe a monaural auditory signal-processing model for the perception of coloration. The model gives a central spectrum display of a stationary input signal. The central spectrum level for a nerve fiber tuned to a given frequency is computed as a combination of the average firing rate and the firing synchronized to the center frequency of the nerve. The model incorporates a critical-band filter bank, steady-state representations of the average and synchronized firing rates, and temporal integration. The central spectrum model, when used to process simulated data, accurately predicts the perception of coloration in filtered Gaussian noise.

Auditory Perception↗