Right you are the serial numbers are 84T227 and 84T228. 227 also has MK J stamped onto it. I just tired to find something to interpret the code, but as far as got was that they were manufacture in '79. I'm moving in the next few weeks and don't really want to take them with me. I'd like to give someone who would appreciate them a good deal. I should let you know they been in my attic for about 15 years. They sounded great when they went up there, but I'm not going to wire them up for a while until they get acclimated. I also have a newer (relatively) Sony STR-DH500 AV receiver, a 5 speaker Polk Audio set, a Pioneer CT-S507R cassette deck, a Onkyo CP1116 turntable, and a older Pioneer VSX-454 Dolby Pro_Logic Receiver. I got the impression from one of your other post that you might have a shop. I'm having a little bit of a hard time determining the worth of the speakers, so I'll say $400.