Relationship of amplifier sound to transformer quality?

Is this significant?
That's perfect. Thank you.
As above.
Paralleling power supplies is a problem waiting to happen.
Duly noted. I hope not. In any case, I will discover how closely matched they are first. If they are more than a few mil.v apart I think I will leave them alone and acquire a big transformer to experiment with instead. The Meridian 105s are serious world class amps even now, 40 years later. But their elegant compact form factor renders them a bit lean in the bottom end which is what consensus was back then and I'm very interested to find out what they can do with no holds barred.