I'm looking for some info on a quad of Celestion G12 80 speakers. The numbers are T 3103 cone number 444. They date to 1981. I'm guessing these are the bass (55hz) version of the G12 80? I've seen other G12 80's but I believe they had the 1777 cone. That was sometime ago so I'm not sure about that. Any help would be appreciated. Thanks.