Robust real-time sound pressure level stabilizer for multi-channel hearing aids compression for dynamically changing acoustic environment

Abstract

Multi-channel compression is one among the most popular techniques of hearing aids of mapping the wide dynamic range of speech signals into the reduced dynamic range of hearing impaired listeners effectively. Most of the Multi-Channel Compressors are particularly designed to manage certain loudness pattern, but it's quite difficult to efficiently capture the dynamically changing acoustics in Real-Time. The proposed method circumvents this problem by providing a contraption to estimate the fluctuating sound pressure level (SPL) and converting it into the desired SPL suitable for Multi-channel compression. This objective of stabilizing the SPL is achieved by incorporating a rapid voice activated detection (VAD), a root mean square (RMS) estimator, a moving average (MA) rectifier and a SPL regulator. Proposed SPL Stabilizer provides the hearing aids compressor with a comparatively constant SPL level input in Real-Time, and there by improves the quality and intelligibility of compression output signal.