The simplest and most effective optical illusion ever is the Necker cube. Which side is in front? The answer is both and neither. Very Zen.
In the process of gathering musical simples, I found a P-Funk loop with a similar effect. It’s a keyboard lick from “Do That Stuff” from The Clones Of Dr Funkenstein.
This loop is best known to the hip-hop generation as the basis of “Funky For You” by Nice & Smooth. Greg Nice begins his first verse halfway through the loop. Apparently he hears the E chord as being the beginning of the loop.
I had heard “Do That Stuff” many times before ever hearing “Funky For You,” so to me, Greg Nice seems to be starting in the wrong spot. However, when I posted my transcription of the loop, I heard back that I had it backwards. If you heard Greg Nice before P-Funk, you probably agree with his interpretation.
What is it about the loop that makes its front and back halves so interchangeable? Usually these kinds of phrases start on the tonic chord, the root, harmonic “home base.” The tonic chord of “Do That Stuff” is E, but in the loop, the E chord is in the back half of the loop, which is a metrically weak spot. If you walked into the studio while the loop was playing, you might well intuit that it had the tonic at the beginning of the loop as would be more usual.
“Get Lucky” by Daft Punk is based on a similarly ambiguous pattern. It’s also a four-chord loop: B minor, D, F# minor, E. It isn’t at all clear which of these four chords is the tonic. I hear it as F# minor, which is in the same metrically weak location as the tonic in the “Do That Stuff” loop. If you used the “Get Lucky” loop as a hip-hop sample, and your emcee wasn’t familiar with the original song, they’d have a fifty-fifty chance of coming in on the third chord.
The other musical Necker cube that leaps to mind is the omnipresent I-V-vi-IV progression. It can be flipped around to form the equally plausible vi-IV-I-V progression, as heard in the later part of the “Four Chords, Thirty-Six Songs” video.
If you can think of any other musical Necker cubes, post them in the comments.
Thank you the astute naming of something I’ve experienced but couldn’t put words to (at least not well.)
Here’s an example (I think): https://mixelpixel.bandcamp.com/track/fake-violin-solo
I’ve heard this song many times yet it isn’t until the vocals come in that I can adjust my sense of rhythm to catch the correct beat of that leading synth loop.
I think Led Zeppelin’s Kashmir may also have a Necker Cube thing with the scale-walking backing chords.
Talking Head’s Once in a Lifetime seems to drop a beat as it moves into the chorus part of the song; the bass line stays the same but the song’s rhythmic emphasis is shifted.
Not sure these are exactly the same phenomenon, but similar:
The verse of I Knew You Were Trouble (Taylor Swift) and the chorus of Try (Pink) sound two beats out of phase to me. This is sort of a zoomed-in version of the same phenomenon.
The verse of Pumped Up Kicks (Foster the People) could plausibly be in the key of the first minor chord (let’s say Dm, can’t remember the key of the song). But once you hear the chorus, with a very similar progression to Get Lucky, it’s clear the song is in C and it’s very difficult to hear the next verse in Dm.
I’m sure I have plenty more, these are the first few to come to mind.