Algorithms ranging from dynamic-range compression and directional microphones to sound classifications and binaural noise suppression are explained, providing a comprehensive explanation of signal processing approaches used in modern digital hearing aids. Because the book is intended for professional or graduate students in hearing sciences, little review is given to the mathematics applied in the topic. Chapter topics include a history of hearing-aid technology, signal processing basics, the electroacoustic system, directional microphones, adaptive and multimicrophone arrays, wind noise, feedback cancellation, dynamic-range compression, single-microphone noise suppression, spectral subtraction, spectral contrast enhancement, sound classification, and binaural signal processing. Although the author both works for and received support from a particular hearing aid manufacturer, the focus is not on commercial products or implementation but rather the principles and approaches used for different signal processing algorithms. Annotation ©2008 Book News, Inc., Portland, OR (booknews.com)