Yes it is a AA920. The tube complement is 2 12ax7, 1 12au7, 1 5y3gt, 1 6c4, and 2 6L6gb. Right next to the capacitor cans is a potentiometer. All of the writing is gone. Is that a bias voltage adjuster? The imprint on the back says 110w. I assume that's consumption. Interesting of the input selector there are tape amp/aux/radio/tape head?/nartb?/RIAA/AES?/LP. Have any ideas on the ?