Digital signal processing applied to the equalization of the loudspeaker-room interaction

Abstract

In the presence of reflecting surfaces, the direct or on-axis sound of the loudspeaker will be summed with the reflections of all the off-axis response and form the total response at the listening position. Room modes which occur in any closed room, no matter what the shape and degree of sound absorption applied, also affect the response at the listening position. The desire to improve the measured as well as perceived response at any listening location from any typical loudspeaker position led a group of loudspeaker manufacturers to form a research consortium (CARC) and participate in a joint venture with the NRC. The collaboration was called the Athena project, whose purpose was to improve the overall quality of sound reproduction by loudspeakers in rooms with the use of digital signal processing. This paper sets out to demonstrate the technical performance of the current CARC/NRC DSP engine and its associated software