ABSTRACT
Loudspeaker design is a mature technology. For some, loudspeaker design is portrayed as an art and the listening experiences that result are described in poetic terms. In the intervening years many others have added innovations to loudspeaker design and aids to making engineering measurements. When anechoic measurements were made on some highly rated audiophile loudspeakers of the time, the results were disturbing. Acoustic Research deserves credit for being pioneers in attempting to relate in-room measurements to measurements pertaining only to the loudspeaker and having the candor to publish honest and accurate data. Measurements on single axes show acoustical interference that is disturbing to the eye but not necessarily evident to listeners in normally reflective rooms. Edgar Villchur of Acoustic Research, was an enthusiastic supporter of measurements, including the idea of integrating on and off axis radiated sound in a measure of the total sound power.
