Lowering the noise floor


I am coming to the conclusion that success in home audio reproduction is largely about lowering the noise floor. There are so many different types of “noise”, from so many different sources, that we only really “hear” by their absence.

Those components, cables, accessories and tweaks that SUCCEED at lowering the noise floor, can, and do, dramatically increase sound quality. Sometimes the type of “noise” dealt with is controversial, or not (yet) widely recognized as being a problem. Sometimes the explanation of how a product works is dubious. Sometimes the way it is marketed reeks of “snake oil”. Sometimes the reviews singing its praises go over the top. While these things will certainly put off some prospective purchasers, they do not negate the audible results that are there for anyone open to hearing them.
tommylion
I have come to the conclusion that success in home audio reproduction is largely about speakers & room treatments.

Lowering the noise floor (EMF noise) can be very useful for digital audio - the most critical issue is to ensure galvanic isolation.

An isolation transformer for the whole thing is usually a good idea.  Dedicated lines are costly unless you are doing new construction anyway.
Power supply indeed. But also power cords and cables. I think of a power cord as an extension of the power supply. As for the cables, especially interconnect cables, it is quite obvious too. XLR cables have no inherent advantage with short lengths.