Thanks for the input...just what I was hoping to hear....regarding years of R&D....it has been sometime since
I biased a transistor amp (an old 2N2222 I think it was back in the day). I did a few minor tests...
  1)  tripled the capacitance on the +/- of the ps.....no difference
  2)  disconnected the final amp stage and the hum quieted slightly...not enough to get excited about...
  3)  reconnected it and disconnected a previous stage...still not much difference
  4)  concluded that its inherent in the design (easy way out I suppose)
  5)  took all the knobs off and cleaned the entire unit...doesn't look too bad at this point

Think I'll use it for areas with higher noise floors (not the bedroom!)
Thanks again for the input...greatly appreciated...

Thanks for the input....
  It hums no matter where in the house I plug it in...and the comment about battery powered cube (and/or remote transformer/dc supply) I think
explains a lot....
  I'm not sure what i can do about the audio grounding but I can add more ps filtering....think I'll give that a go....shouldn't be too difficult (famous last words!)
Thanks again

Firstly...thanks for the forum...greatly appreciated....have an operating question about the Champion 30....for a number of years I have used a Roland Micro Cube and for bedroom practice it seems fine....meaning for me its quite when I want it quite....ie...no hum....well I was given a Champion 30 some time back and have blown the dust off it and, for very clean warm jazz kinda stuff it seems to sound quite nice....except for a slight but noticeable (at least in a very quite bedroom) hum (not quite as loud as Marty McFly standing pic in hand in front of Doc's 6' speaker)....knobs have no impact and the amp does sound very nice otherwise.  My question is.....is this normal for this vintage/era amp? Are hum-less amps the exception and not the rule? Maybe time to throw a blanket over the unit as a hum notch filter?
Thanks again for the forum....would appreciate any comments.
Tom