Sound quality centered measurement technique over 40+ years: experiences and perspectives

The author’s life work in acoustics and sound quality, though continuous over more than 40 years, has followed a number of parallel and nonparallel paths all involving measurement technologies and their evolution. The illustrated discussion begins at the Research and Development Division of Kimball International, Inc. (Jasper, Indiana) in 1976 with piano research using a Federal Scientific Ubiquitous analog real-time FFT analyzer and Chladni-plate-mode studies with fine sand and high-speed photography of sound board modes excited by various notes and damper pedal positions. It continues at Jaffe Acoustics, Inc., a concert-hall-specializing consultancy in Norwalk, CT, with early-reflection plotting using a parabolic microphone on an altazimuth angular-readout mounting and either photographing oscillograms, or running a high-speed paper chart printer, assembling “wheel plots” incremented every 10 degrees in azimuth and altitude to map reflection patterns. Involvement with binaural technique began for me in 1987 and led me into the automotive industry, whose SQ evolution and that of HEAD acoustics will be outlined along with an even earlier side-branch courtesy of James Shedlowsky (GM retired): a photo-archive of GM pseudo-binaural and binaural techniques and jury evaluations starting in 1953 which has been presented in an earlier Noise and Vibration Conference’s Science Fair.