Am I hearing the effects of "clean sound"?

Recently,the weather down here in South Florida has been-in a nutshell-perfect.
Not too hot, not to cold, low humidity, nice breeze.
With this type of weather, there's not a need for us Floridians to crank up the ac.
Leaving the windows open does the job.
When I arrived home Saturday night after watching some football with some friends both my wife and son were asleep and my daughter was staying over a friends so of course it was time to crank up the system.
What I heard set me back in a very good way.
Music flowed effortlessly and clear.
Probably the biggest improvement I heard was a lack of grit, if you will, with the music.
Presence was stronger without any rolled-off highs.
It sounded nice!
Do you think that because of the "cleaner" lines and also it was somewhat late, around 11:30 or so, that the music was some what "cleaned up"?
Is this what one could possibly hear with dedicated lines?
As always, thanks for your input.