The loudspeaker as a measurement sweep generator for the derivation of the acoustical impulse response of a concert hall

Precision digital technology has made the measurement of an accurate and representative acoustical impulse response function (AIRF) difficult. In using the exponential sine-sweep technique to record the acoustical parameters of a concert hall, there are several measurement issues that need to be resolved in order to determine an appropriate set of international standards. One of the issues is the type of the loudspeaker to be used as the source generator for a signal sweep. This paper presents a discussion on the role of the loudspeaker in the AIRF measurement process. Two high-quality loudspeaker systems are used and evaluated: one a direct-radiator-type near-field studio monitor, and the other a high-frequency (HF) compression driver and horn-loaded sound reinforcement system. Through an analysis of specific loudspeaker characteristics and measurement results, it is shown that the HF horn-loaded system is a suitable reference monitor for acoustic measurement of concert halls.