Coherence measurements in hearing instruments, using different broad-band signals.
In this investigation the effect of different broad-band test signals on non-linear distortion in hearing instruments was examined using coherence measurements, and the interaction between different test signals and types of automatic signal processing is explored. It is concluded that the use of coherence measurements to quantify non-linear distortion in hearing instruments is only valid for instruments without automatic signal processing. This limitation arises because interaction between type of test signal and the automatic signal processing used causes system time-variations, which influences the measured coherence function in an uncontrollable way.
Dyrlund
O
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Technical-Audiological Department, School for Deaf and Profoundly Hard-of-Hearing Children (Fredericiaskolen), Fredericia, Denmark.
D000161:Acoustic Stimulation; D000669:Amplifiers, Electronic; D004867:Equipment Design; D005260:Female; D006309:Hearing; D006320:Hearing Tests; D006801:Humans; D008297:Male; D009622:Noise; D012815:Signal Processing, Computer-Assisted; D013067:Speech Perception / Q000502:physiology*