At 08:43 PM 4/13/2011, Alistair Bell wrote:
>Shield on or off makes no diff. to my problem. My noise comes through
>all inputs.

It wouldn't.  AM radio only.  Go get that ground loop isolator and
stop torturing yourself. ;-)

d
ps - the amp in that diagram costs three grand for 30 watts/channel
and has ten tubes in it...you can believe that Mr. What-his-name
doesn't want to hear about input noise issues from his gold-plated customers.