The Concert Grand was the crown jewel of Bozak speaker systems since its introduction in 1951. This refrigerator-sized speaker system originally contained four B-199 12" woofers, one 8 Ohm B-209 6" midrange driver and eight tweeters. The B-310 and B-310A were the mono versions in which the tweeters were arranged as a sector of a sphere for widest distribution of high frequencies. The 'stereo' B-310B and B-400 had the eight tweeters arranged in a vertical row. All Concert Grand models starting from the B-310A contained two 16 Ohm B-209 midrange drivers. The Concert Grand loudspeakers were designed to fill large spaces and were not at their best with listeners closer than 20 feet away. In 1965, a pair of B-410 Concert Grands cost US$2000. Such a high price limited ownership to a small number of hi-fi aficionados and audiophiles. The model line continued to be manufactured by Bozak until 1977. Henry Mancini and Benny Goodman, good friends of Rudy Bozak, owned Concert Grand speaker systems. Jack Webb put a pair in his Mark VII Productions listening room.