"This book is written with the author's boundless enthusiasm both as an educator and a leading researcher backed with his deep affection for acoustics. As an educator, he spends many pages on the equivalence between a cascaded mass-spring system and one-dimensional wave propagation with keywords such as energy balance and eigenfunctions and eigenfrequencies. These keywords are common throughout the whole 15 chapters. As a researcher, he deals with signals in the acoustic space in the time and frequency domains, with modal expansion and Green's functions, with the ray tracing and wave-theoretic methods, with propagation and reverberation phases, with poles and zeros of transfer functions, with amplitude (magnitude) and phase characteristics, and with minimum and non-minimum phases. Interesting and advanced topics in the book are: (1) distribution of eigenfrequencies in one, two, and three-dimensional spaces, (2) derivation of Green's functions from orthogonal eigenfunctions, (3) reverberation decay characteristics in "almost-two-dimensional" reverberation fields, (4) chaotic properties of semi-stadium fields, (5) cross-correlation functions between two points in random sound fields, (6) phase responses and distribution of zeros of transfer functions in three-dimensional fields, (7) speech signal envelope recovery from phase using short time windows, (8) clustered line-spectral and clustered time-sequence modeling, (9) control and modification of reverberant sound paths by inverse filtering. The author's broad research activities noted above are supported by his collaboration with researchers worldwide in various fields. This book is recommended for people who are going to start their careers as acousticians as well as those who aim to accomplish leading research in the field of sound and signals. Minor English problems are easily outweighed by the invaluable content of the book.

" (Hideo Suzuki, former Professor at Chiba Institute of Technology, August 2013).