Questions concerning Celestion A6 Subwoofer

A local dealer has a non-used Celestion A6 subwoofer from the 1990's for sale. He says it's a great sub for music and movies, but doesn't know the specs. It's 13x24x17 with a floor facing port. I have not listened to it yet. I can't find it on the net. Does anyone know about this sub. I believe that it's the same vintage as the Celestion A1,A2,and A3. I have a PSB Surround system with an old Velodyne C-80 sub. My other choice is a PSB sub such as a Subsonic 5i or 6i. I don't want to miss a deal but don't want to buy less than PSB offers. I listen to classical, jazz including Patricia Barber and Diana Krall, and the Eagles, Dire Straits, and some other rock. My main PSB Stratus Bronzes go down to below 40 Hz. On this upstairs surround system, I listen to 80% 2-channel and 20% movies. The sub would be for movies and to tighten up the bass on the Bronzes. Thanks.
John Dean