Hey again! I think it's a '73 SVT, but have no way to know for sure. The serial number on the aged yellowed paper glued inside the head says: 48631. Anyone know what year it might be?.., besides going from this link dating ampegs, it narrows it to '72-75. http://users.aol.com/bluemuse/dating.html Next if anyone could explain what these 2 jacks on the back can be used for: "EXT AMP" I guess: to power an external power amp? Could it also be used to line-out to a direct box? Thanks!