I have an old reverb unit, and a couple of questions. It is a "Premier 90" model made by the Multivox Corporation. The reverb effect is very weak. I replaced the filter caps and installed a 3 prong power cord which tamed the severe buzzing that it had. I have also replaced the tubes. Does anyone have a schematic for this unit? Also, it has a long spring reverb pan (2 springs). I can't see a name on it but there are two sets of numbers AO-23580-10 and 1122-6314. Any help on replacing this pan? I do get a "crash" when I tap on the pan, but the effect is very weak. Any help would be appreciated. Thanks.