Slipknot is not a safe pick for a blog about metal. Lots of aging Gen X metalheads have hated Slipknot since the day it was created and refused to accept it into the fold. Why? mumble mumble “it doesn’t sound like metal” mumble mumble “the masks are a gimmick.” Well, you got me on the second one. The masks sure are a gimmick—but metal has always been full of gimmicks. Kiss’s make-up and secrete identities were a gimmick. Twisted Sister’s cross-dressing getup was a gimmick. Yngwie Malmsteen’s gorgeous curls and bundles of bangles and self-comparison to virtuoso violinist Niccolo Paganini is a gimmick. GWAR’s insane latex alien costumes are DEFINITELY a gimmick. And if you want to get really meta about it, Metallica’s no-makeup denim-‘n’-leather longhair image is also a gimmick, in a way.

But the first one isn’t true: Slipknot sounds like metal. Or at least, for listeners who don’t throw a fit and refuse to listen, Slipknot’s music does all the same things that metal does for you, and does them in spades.

If Slipknot were just another metal/metal-adjacent band, there wouldn’t be much of a story. Some think it’s metal, some don’t; you say tomayto, I say tomahto. We’ve all heard that before, a hundred or a thousand times.

But there’s something more to it than just a squabble over genre boundaries: Slipknot’s best songs are true neck-wreckers. Simply put, Slipknot is one of the heaviest bands of the late twentieth century, whether you like them or not. So why are Slipknot songs such bangers?

I could talk about their pummeling drums, their racing riff tempos, their rough-voiced melodic singing and animalistic screams, their sludgy gut-busting guitar tone. But song structure is also part of the equation. And since this is a music theory blog, song structure is what I’m best positioned to talk about.

What kind of song structure makes a song a real banger? I think that’s the wrong way to ask the question. There isn’t one magic bullet strategy for writing songs. And I would argue it’s not really the song structure itself that makes a song heavy, but the way you inhabit the song, the way you experience it, your headbanging and stomping and fist-pumping, your anticipation of breakouts and breakdowns, the sound of blood thundering in your ears and the feeling of your heart hammering in your neck.

The song structure doesn’t create heaviness directly, but creates a scaffolding for heaviness. If heaviness is like floodwaters, song form is like the pattern of valleys, levees, diversion canals, and spillways that guide the raging torrent. So the answer to the question “What kind of song structure makes a song a real banger?” is something like: song form that encourages you to participate with your whole body, songs that invite you to hear and imagine thrilling plunges into darkness, songs that invite you to embody ecstatic thrashing transcendence.

Here I’m riffing on an idea from Glenn T. Pillsbury called “energy cycles,” an idea that the power of thrash metal music revolves around changes and cycles of physical energy we experience through body motion and physical feelings while listening. ((Pillsbury, Glenn T. 2006. Damage, Incorporated: Metallica and the Production of Musical Identity.))

“I theorize the musical aesthetic of thrash metal as movement through cycles of energy working on many different levels to focus power and intensity into bodily experience. These range from the meta experience of the mosh pit and the insistent speed of the beat that assaults and affects the bodies of the performers and audience, to the particular physicality of playing riffs using a heavy amount of palm muting […]. Moreover, Chapter 1 explores how the various combinations of rhythmic intensities in the guitars and drums underlie most of the formal characteristics of thrash metal songs in ways much more pronounced than in other styles of rock. The effect of the changes from section to section is also phenomenological, and our understanding and experience of them depends greatly on the temporal thickness of subjectivity. Ultimately, rhythmic intensities do not signify nearly as strongly by themselves. Rather, the changes in intensity provide the crucial context for their signification, and the various contexts then create the cycles of energy that make thrash metal songs so effective.”

(Pillsbury 2006, p. xx)

These feelings of physical motion or impact are structured by the music, and Pillsbury discusses several levels of structure, from individual notes felt as blunt physical impacts, to “verse/chorus energy cycles” and whole-song form. A verse/chorus energy cycle is a sense that the song’s sections build up energy from the verse into the chorus. This increase in energy towards the chorus is a common tendency throughout rock and pop music, but metal of course has its own devices to amplify this flux, and its own ways of expressing and experiencing the energy at those peaks. Lady Gaga songs might also have a verse/chorus energy cycle, but they don’t have blast beats or mosh pits.

One way that Slipknot creates these verse/chorus energy cycles is by increasing intensity in drum patterns between sections. Another strategy they use is to increase the number of instruments and the levels of distortion or noisiness; a music theorist named Ciro Scotto has written about this strategy, describing patterns of increasing intensity in timbre through an analytical framework called “contour theory.” ((Scotto, Ciro. 2016. “The Structural Role of Distortion in Hard Rock and Heavy Metal.” Music Theory Spectrum Vol. 38 No. 2.)) In their song “Duality” you can hear how they start out with a whisper, then add in one guitar and a piano, slowly building up to power chords and thundering toms and finally to a full-blown all-out breakdown. I think there’s also something to be said about the way Slipknot uses different kinds of syncopation and other rhythm patterns to generate forward momentum.

But today I’m not talking about any of those, I’m talking about musical form. Slipknot does something else in “Duality” that creates this sense of relentless, inexorable building. But it’s pretty subtle, and you might not have noticed it.

In “Duality,” the length of each riff gets shorter throughout the verse/chorus cycle. See the chart below. The opening riff of the song is four measures long, and it structures something that sounds kind of like an Intro Verse but ends up being a foreshadowing of the Chorus. The second riff is only 3 measures long, and structures a kind of unstable instrumental Pre-Verse section, building energy towards the Verse. Riff 3 is 2 measures long, and functions as the Verse, increasing the pace further. Riff 4 is really only half a measure long, blowing off the safety valve of the song’s pacing. This section functions as a Pre-Chorus, and you can feel that it won’t last long, that it can’t last long.

With each subsequent riff shorter than the previous one, this riff order gives the song a kind of structural acceleration that builds relentlessly towards the Chorus. Finally, the cycle climaxes in a Chorus based on a highly distorted version of the opening riff. The switch back to a 4-measure-long riff feels like a release of pent-up energy, a cathartic explosion of sublimated aggression. Unlike the version of this riff at the opening of the song, which felt tentative and subdued, the Chorus at 1:23 has come after this long series of recursive increases in pace. That buildup turns the same rhythm that was relaxed in the Intro into a powerful demonstration, a bold and fearless open stride after the harried pace of the Pre-Chorus.

After repeating this verse/chorus energy cycle, the song plummets into a Breakdown at 2:25. ((I’m eager to recommend Steven Gamble’s excellent recent (2019) article “Breaking down the breakdown in twenty-first-century metal” Metal Music Studies Vol. 5 no. 3.)) This breakdown uses the unstable Riff 2, building on our previous association of that riff with the anticipatory Pre-Verse function. Here the half-time drum patterns clearly frame the section as a Breakdown not a Pre-Verse, but it resonates with that accumulating, anticipatory function, creating a relentless Breakdown that (unlike some song-ending breakdowns) feels like it naturally builds towards a reprise of the Chorus. And like any Breakdown, this section invites you to experience peak physical intensity, unleashing your wildest moshing and thrashing.

And then a second Breakdown happens at 3:40, even heavier! The building energy doesn’t let up, compounding on everything that’s come before, egging you on and inviting you to headbang even harder than you did for the first Breakdown.

That relentless acceleration throughout “Duality” is part of is why this song is so heavy; through structural acceleration and then a double-breakdown, it invites you to reach a zenith and then ascend beyond it, surpassing your own maximal efforts. Every time I listen to this song, I embody the accelerating pace of the verse/chorus energy cycle, the relentless buildup across the song gets me worked up to a frenzy, but I always forget that there’s a second Breakdown, and give it all for the first one. But then the music ups the ante, blowing through the ceiling.