Awesome acquisition! Welcome the the MCS 3125 club. I hope you enjoy your's as much as I enjoy mine.
If you are going to really listen loud, I would re-arrange your set up. Get the speakers away from the turntable. Especially important, because unlike most of the better NEC made pieces, the 3125 doesn't have a subsonic filter. You might be able to insert one in one of the tape monitor loops. Something that cuts frequencies below 15Hz will help out a lot if you plan to listen to records at high volumes.
That MCS catalog shows some of their 1981 offerings. When I was in college, I collected those catalogs. Befriending the salesman in that department landed me the catalogs from 1979, 1983, 1984, 1985, and 1986. AK member woofercooker also knew this same salesman, and got catalogs from 1981, 1982, and 1983. He was nice enough to let me borrow them, and scan them. Lots of cool info. and specs - but not every model made it into these catalogs. And since their art department put these catalogs together, there are a few mistakes and incorrect specs listed. To get pricing information, you had to refer to the huge JC Penney catalogs. I have a few, and it's fun to see what was offered. Some of the pdf files are a managable size, but some are enormous - too big to email, or post.
Now track down some 8228s and have some major fun (nothing against your 8330s, though)!!
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