I don't. My issue with the deeper understanding that you refer to is that I don't agree that it really matters in creating "meaning" or something great and transcendent of time. I fail to see any of "musical semantics" and whatever else in something like Beethoven's 5th or Fur Elise. The latter could've been about anything else for all I know. It could've been titled differently, and it would've been just as great. I can't remember which piece it was, one that was supposed to be about the moon, but a friend of mine told me that he was listening to it while driving and his daughter was in her car seat and she said "It sounds like the moon, daddy." So, obviously, we have a composer who is capable of conveying these semantics to even children. The idea that this inherently elevates his work to some higher value is absurd; it's just snobbery. Much like any other form of symbolism, like the color red and what it "means" are simply tools you can use to convey a message. But they are largely cultural, and do not necessarily have universally understood meanings, and such meanings are also dependent on the individual. I could sit here and probably derive some perceived "deeper meaning" in this girls music, and as long as I use enough persuasive, florid language in my argument, I could prove nearly any point I want to make. "See! There is a meaning! You plebs just don't notice it!" The idea that her music, or any music, must have this sort of symbolic relevance and "say something" to be "art" is little more than intellectual masturbation. I don't even mean to insult anybody with that, but that's just the way I honestly feel about it.