Balanced vs Unbalanced?

IMHO, Audio merits are based on scientific merits. There is no magic here.

BTW, this topic has been debated for the Nth times. Search is your friend, my
friend.

"Balanced" is another 'selling point'. It 'can' be good, or it can just be useless nonsense.
The majority of 'add on' balanced is done with smoke and mirrors: just an op amp adds an inverted signal at the end of a nonbalaced chain, just so a balanced connection can be used. Then, at the far end, the balanced connection is wasted and turned back into an unbalnced signal to amplify.
The REAL stuff that is fully balanced from start to finish is "the real deal" and will be better (usually, and it costs twice as much too)
The ONE advantage for an opamp sort of balanced connection is if the cable has to be long, or if a lot of RFi/ hash noise in area.
i have an op amp out to an op amp in (Bryston) and still use the balanced because it is a 20 plus foot run. It is not really better.. just no worse.
IMO "balanced" using op amps is just marketing BS.
it is no worse than unbalanced in practice, even though it adds the opp amp into the mix.

According to McIntosh's manuals with their balanced gear, if your interconnect cables are 6' or under, unbalanced connections are quite satisfactory. However, longer than 6', a 40db advantage in noise reduction is possible. Whether you can actually hear any difference between the two types is subjective.
Here's another one--why is McIntosh the only company to use autoformers, when other companies (i.e. CJ) don't use them? Any sound differences?