I used to concur with the idea that "musical" and "emotional" were really stupid ways to describe audio.
But lately I've sort of made a turn-around in my opinion. Here's my rationale:
A good musician who makes beautiful music has a particular musical sound in his/her head when playing music. Believe me, I know from experience that that's often the difference between good and great musicians; the great ones know how to hear better IN their head. Some musicians can move you emotionally JUST by the quality of their sound. I'm thinking of violinists like Heifetz. He'll mesmerize you with that intense sound alone, never mind phrasing and all those other "musical" things. So, "musical" can be applied to just a single sound. An unstructured sound like breaking of glass is noise. When a musician shapes sound into something aesthetically pleasing, it's music.
If that is true, then audio gear that keeps that structure intact is in my book, "musical". I've heard audio gear that utterly destroys the emotion that the musician was trying to convey. It might do it by having harsh treble peaks, recessed mids, whatever.
So in theory, "musicality" should be equal to "neutrality", since ideally, we'll hear all the emotion the music have to offer without adding or subtracting anything.
Unfortunately, there is no such thing as a perfect recording. That's why we have to play around with colourations in headphones/amps/sources/cables to try to re-create the emotion as much as possible.
That's just the way I see it.