The audience wants a groove. You can add interest to a song by changing the rhythmic figures in it, but if you mess with the very bottom of the groove, the tempo, in midstream, you ask your audience to make a difficult adjustment. Why would you want to do that? Well, for experiment’s sake, or for variety’s sake, or maybe to make an expressive point. But tempo is more fundamental than anything else in determining what feels right in a piece of music. How, then, could you shift tempo in a way that felt exactly right? And—to make the challenge even harder—how could it be done without a transitional acceleration or deceleration?
The tempo shifts in “Suite: Judy Blue Eyes” (Crosby, Stills & Nash) are nice, and by now we can all easily follow them, but the point is, it’s a suite. It’s like listening to several different songs in a row. In fact, many of the songs I can think of with nice tempo shifts are like suite experiences. I’m looking for an example of a tempo shift that unarguably makes a single-song experience great.
If there is a cogent tempo shift, do you suppose it follows some implicit mathematical law, some Golden Proportion? Halving or doubling the tempo would feel smooth, but those changes are pseudo-changes—they just make different selections from the ticks that were ticking all along. How about two-thirdsing or 150-percenting the tempo? Does anyone know how that would that feel? (I’ll tell you: it feels like slowing way down and speeding way up.)
Mathematics is out the window with the clearest example I know of a tempo shift that we consciously expect and enjoy, the verse-to-chorus shift in The Beatles’ “Lucy In The Sky With Diamonds.” It’s also a shift between a circling 3/4 and a loudly marked, linear 2/4 or 4/8, so the faster tempo of the chorus feels like a well-organized blast-off. The increase in speed here conforms to no elegant proportion that I can detect. It’s just . . . faster, not gauchely too much faster or indecisively too little faster; it’s a let’s-get-going faster that we can handle just fine.
For students of time structure, “Lucy” makes a great exhibit of the interdependence of beat, pulse, and measure. Beats are the elementary units of rhythm, the ticks you can keep track of. Pulses are the primary emphases, the whoomps. (Often people call pulses “beats” and measure them in “beats per minute,” as I did myself in the “Killer Tempo” post.) Measures are the basic units of wholeness in rhythmic structure; a measure is your trip to a place where you feel you’re starting over. In “Lucy’s” tempo shift, the beat count goes roughly from 134 per minute to 188, about a 40% change. But that doesn’t mean the tempo is 40% faster, because the pulse rate and the measure structure change at the same time. The new measure that most closely corresponds to the old 3/4 measure is four eighth-notes in two pulses, so we’re talking about measures of 4/8 or 2/4 (corresponding to Lucy in the). The length of this four-beat, two-pulse measure is about 1.28 seconds; that’s just a little quicker than the 1.34 seconds of the previous three-beat, one-pulse measure. The pulses of the new 2/4 are close to double-timing the pulse of the 3/4.
ADDENDUM: Lucy Vodden, the Lucy that John Lennon had heard about, died in London on September 28, 2009. Meanwhile, a newly announced East African fossil ancestor of humanity, “Ardi”, is more than a million years older than the great Beatles namesake “Lucy” the Australopithecus. Do you feel an evolutionary tempo shift?
1. An elegant acceleration can be a hook in itself, as in King Crimson’s “21st Century Schizoid Man.” There’s a nice deceleration of an ultra-pop-rock drum beat right at the beginning of Joe Jackon’s “Hit Single,” as though to say, “We’re slowing down for a moment for a look at this hit single thing.” Another interesting tempo shift hook, but bewildering, is Z Z Top’s sudden change after the chorus of “I’m Bad, I’m Nationwide” to a fast 6/8 for one measure followed by a rapid deceleration in the next measure back to the original slogging pace. It seems to mimic a clutch problem.
2. Allan Moore’s finding is close to mine: “the first verse is in a slow 12/8 . . at 46 bpm, while the refrain doubles the tempo (to 93 bpm)” (The Beatles: Sgt. Pepper’s Lonely Heart Club Band [Cambridge: Cambridge U., 1997], p. 32). His “beats” are my “pulses.” The problem with this analysis is that the felt tempo of the song is obviously not twice as fast in the chorus. Meanwhile, Walter Everett’s beat duration analysis swerves obscurely toward the opposite mistake as he concludes that the chorus tempo is one-third slower than the verse tempo (The Beatles as Musicians, vol. 2 [Oxford: Oxford U., 1999], p. 333 n. 38).