I was recapping my 2 Coliseum bass heads- one is a January of 1972, the other September of 1974. I'm not trying to make any point here, just had them apart and took some shots, and though some of y'all folks might find this interesting, at least a little.
The 1972 has a plywood head cabinet with the rubber handles, the ones with the squate ends. The 1974 is particle board, has not help up as well, and has the leather handles;
The 1972 has (what I think) is a Shomaker or Shomacher transformer, with a 606 code like Fender used. The 1974 has a different code. There's maybe 6-7 months difference between the date code on the transformer and the inspection date on the 1972 Sunn head (Tranny code 26th week of 1971, amp inspected 1/13/1972) and 3ish months difference on the 1974 (tranny code 25th week of 1974, inspection gate 9/11/1974).
The 1974 also has some shielding around the preamp section the 1972 does not have.
Both amps sound great. I haven't modded anything other than to put rubber feet on the bottoms to keep them from vibrating off. They get used with a couple of 118V cabs. The difference between they way they sounded a week ago and the way they sound now after being recapped is really noticeable! The low end, while astounding before is even more astounding!
