Abstract: The stereophonic system includes a pair of right and left channel sub-bass converters in addition to the usual right and left channel main speakers. The main speakers are spaced apart from each other at one end of a space and the two sub-bass converters are spaced apart from each other at the opposite end of the space. The preferred position of a listener is generally between the two sub-bass converters. Each sub-bass converter comprises an inner housing defining a first chamber and a larger outer housing which is inverted over the inner housing, so that a second chamber is defined between the two housings, above and around the inner housing. The lower end of the inner housing serves as a floor contacting base. The outer housing has a 360.degree. extending lower edge which is spaced above the level of said base, so that a generally downwardly directed, 360.degree. extending outlet for the sub-bass converter, leading out from the second chamber, is formed near the base of the sub-bass converter.