Even today, I appear not with an original idea, but with a multimedia realization of a student's original idea. This student (the same one who also suggested the combination of Clapping Music and Rite of Spring chords) recently mentioned in conversation that this passage from Stravinsky's Firebird sounds kind of like audio being played backwards.
This immediately made sense to me - it is quite a striking passage, and there's something about the desperately short phrases, rushing up quickly and falling off little cliffs, that recall the weird effect backmasking generally creates. Part of what makes the music sound so ecstatic is the buzzing background sounds that are hard to process (aurally) as notes on a page; the basic tune (circled in red below) is actually quite lovely and could have been scored in a more traditional Romantic way, but the frenetic orchestration creates the kind of strange aural artifacts that are inevitable and even desirable when applying techniques like backmasking.
You can see above how the simple violin melody is surrounded by quivering distortions of itself; all those nervous pp rests are like fractal replications of the silences that appear at the beginning of the first and third bars - and that's just the upper strings. Check out the full score:
I suppose the most distinctive artifact that comes from actual backmasking is the reversal of the typical attack/decay patterns. Here's what happens when Stravinsky's most famously attacked chords are sent swooshing back to the future:
Trippy!
But in the Firebird excerpt above, the swooshing effects are already there. So, naturally, I was interested in what would happen if Stravinsky's reverse-like music was reversed. While experimenting with this, I also stumbled on a kind of cool visual effect in which the waveforms are superimposed on the score. However, unlike the Rite of Spring example above, the waveforms are not actually aligned with the notes. You can choose to follow either the notes (which are spread across three pages) or the overall waveform which can be seen in full the whole time. It's a little confusing, but I stuck with it because I like the overall visual that's created by the big, messy, symmetrical splash of color across the score. (Viewing in full screen is recommended - the reversing starts halfway through.)
Yes, it still sounds more distorted than the original when reversed, but it kind of works.
When I first started experimenting with this, I had picked a later passage (which is louder and more climactic, but I later realized not quite as "distorted") and had some fun sending Pierre Boulez and his charges back and forth.
The little arrow in the lower right tells you which way the music is going - from about 0:36 on, it's actually pretty hard to tell the difference!