Multiple sound transducer system utilizing an acoustic filter to reduce distortion

Abstract

The present invention relates to acoustic filters for use in combination with a multiple transducer system which includes a low frequency transducer subsystem and a high frequency transducer subsystem each mounted with respect to an axis directed towards the listening environment so as to function acoustically as though having coaxial acoustic centers. Preferably, the acoustic filter is constructed from one or more acoustical elements such as small tubes, narrow slits, perforated baffles, enclosed cavities, and the like combined so as to provide an acoustical impedance which is relatively low for the frequencies produced by the low frequency transducer but which is relatively high for the frequencies associated with the high frequency transducer. The acoustic filter is disposed acoustically between the low frequency transducer and the high frequency transducer so the acoustic filter inhibits the high frequency sounds of the high frequency loudspeaker from being reflected by the low frequency transducer towards the listening environment and thereby results in a noticeable decrease in intermodulation distortion.