[NOTE: It's been a long time since I took any classes in music theory, and even back then I never learned very much of it. So I'm uncertain whether I've used the right musical terminology here when I compare major to minor. But I bet that, if I've gotten it wrong, some of you will be sure to set me straight.]
Someone I know recommended that I watch this video of a version of the song “Losing My Religion” set in a major instead of a minor key:
It’s interesting—although to me the original is much better (no surprise there). The song was written in that first key for a reason.
It made me think, though, of the last couple of minutes of the score of “Swan Lake.” In that lengthy, lovely, and well-known Tchaikovsky work, the musical theme (the leitmotif) that has been played intermittently throughout much of the action changes from minor to major in the last couple of minutes, after the lovers have committed suicide and as the evil magician is defeated by the force and power of their love. Different productions treat the scene differently, but usually, as the music changes key, the magician crumples (a bit like the Wicked Witch of the West at the end of “The Wizard of Oz,” only he doesn’t melt) and the lovers ascend to heaven as the sun rises.
They pulled out all the stops in those days, didn’t they? That’s a lot of images. No wonder the music has to change.
The changeover passage begins at about minute 2:56 in this video. I have to say that the evil magician character, who in virtually all productions seems to skirt the bounds of over-the-top and ludicrous, in this version ends up falling over that line and is actually an absurd and comic figure, which he definitely should not be. I have no idea why they decided to do it that way. But leaving that aside, the rest of the production is fairly decent, and I especially like the effect at the end with the lovers (their spirits, or whatever) united in the rising sun. The rising sun of course is a cliche, but “Swan Lake” is a cliche too, and if they do it well it transcends the cliche aspects.
Anyway, here it is; pay attention to the musical change at 2:56:
[ADDENDUM: As far as those technical musical aspects go, I did find this:
...B minor is the key of the swans' enchantment. Some 60 bars later, when Odette and Siegfried throw themselves into the lake, the music breaks through to B major and Rothbart's tower crumbles; that's when the spell is broken, and that's when Rothbart should die.
So, it's B minor to B major. Aha.]