Something I've noticed that it does for me really well - it communicates ideas, either sometimes in strictly melodic terms and at others both melodic and vocal, that are too profound for language alone to communicate. Emotion generally is a list of abstract and highly charged objects that words can sort of frame but quite often can only offer a shallow hint at the actual content of.
Another thing, and this is perhaps going off the deep end a little, is if the musician or band is strong enough it can sometimes feel like you're hearing the authority of God/god coming through it - whether that's in the sense of a central self type character, a collective unconscious, perhaps defining God/god as the most simultaneously sublime, beautiful, and terrifying thing you could imagine, whatever it is it can feel like something's thundering forth that's larger than human and in a technical sense I think that's correct because especially when you have two, three, or more really strong musicians get together and even further accelerate each other you'll get a result much larger than the sum of it's parts. Back in the mid 2000's I would have said Muse was a good example of this, Sublime, Tool, or Jane's Addiction back in the 90's, most recently I think Submotion Orchestra nailed this with their Kites album, Sevdaliza took aim at it with ISON, and different bands seem to nail this one in their own distinct sort of way where the musicians seem to practically deify the authority already latent in the vocalist.
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The loneliest part of life: it's not just that no one is on your cloud, few can even see your cloud.