the first aspect of a resolving system is that it reveals differences between recordings and is able to allow each recording and performance to be unique. differences become easy to recognize. the system is a chameleon and can relate all aspects of the performance properly with coherence and balance. the musical differences are not obscured by system and room limitations.
the same things that show differences between recordings, also result in greater musical involvement, although that is not really the same thing as resolving.
the opposite of resolving is that the colorations and distortions on the system and room obscure and veil musical distinctions.
it’s normal for systems with minor colorations or distortions to become worse as the music volume increases as the small issues start to get in the way of resolution. so what is resolving at moderate listening levels is not resolving at higher listening levels. this is a lack of headroom in the signal path or acoustics.
so the idea of a resolving system is variable as to how much dynamics it can handle before it falls apart.
the best systems hold together at full tilt bogie levels.
there are matters of taste involved in tonal differences between systems. when you stray from neutral, then at a certain point of scaling there will be issues. systems tuned for particular music can become out of sorts when pushed. but the listener might do that intentionally. it’s not one size fits all. tuning for a desired coloration simply has consequences.
some gear and speakers do have higher resolution as pieces of a system, which can allow for a higher ceiling of resolution all other things being equal. but a resolving system is much more than that.
$400k speakers and $200k amps thrown together in a bad room can suck. good sound is not an accident. or just dollars thrown around is never proof of anything. yet better gear can take you further, when it’s used effectively.
some media has more resolution, some formats have more resolution. garbage in garbage out. so what you feed your system can limit how resolving it is.