This paper presents a new time-variant reverberation algorithm that can be used in reverberation enhancement systems. In these systems, acoustical feedback is always present and time variance can be used to obtain more gain before instability (GBI). The presented time-variant reverberation algorithm is analyzed and results of a practical GBI test are presented. The proposed reverberation algori...

Reverberation corrupts harmonic structure in voiced speech. We observe that the pitch strength of voiced speech segments is indicative of the degree of reverberation. Consequently, we present an estimation method of reverberation time (T60) based on pitch strength. The pitch strength is measured by deriving the statistics of relative time lags, defined as the distances from the detected pitch p...

culation by the aid of a reliable formula, then, is an important aspect of applied acoustics. A reverberation time formula enables one to calculate the reverberation time once the volume, surface area and average absorption coefficient of the surface of the room are known; or if the reverberation time is measured it enables one to calculate the average coefficient of absorption of the surface t...

The major problem for active sonar systems operating in shallow water is the detection of target in the presence of severe bottom reverberation. The focusing capability of a time reversal mirror (TRM) suggest two different approaches to this problem. First, a TRM focuses acoustic energy on a target enhancing the target echo while shadowing the boundaries below and above the focus in an acoustic...

Byzantine chants constitute a form of monophonic vocal music characterized by lengthy phrases and by musical scales with intervals smaller than the western music semitones. Byzantine churches have extremely long Reverberation Time and their acoustics is dominated by the contributions of the diffuse sound field. Thus, the sound character of Byzantine chanting is closely linked to the acoustic re...

Speech signals recorded with a distant microphone usually contain reverberation, which degrades the fidelity and intelligibility of speech in devices such as ’hands–free’ conference telephones, automatic speech recognition and hearing aids. One important effect of reverberation on speech is overlap–masking, i.e. the energy of the previous phonemes is smeared over time, and overlaps following ph...

Some hearing-impaired persons with hearing aids complain of listening difficulty under reverberation. No method, however, is currently available for hearing aid fitting that permits evaluation of hearing difficulty caused by reverberations. In this study, we produced speech materials with a reverberation time of 2.02 s that mimicked a reverberant environment (a classroom). Speech materials with...

Speech perception runs smoothly and automatically when there is silence in the background, but when the speech signal is degraded by background noise or by reverberation, effortful cognitive processing is needed to compensate for the signal distortion. Previous research has typically investigated the effects of signal-to-noise ratio (SNR) and reverberation time in isolation, whilst few have loo...