hey, welcome to 12tone! to borrow an observation from my friend Polyphonic, there's lots of
bands who could claim to have invented metal, but there's no one who could claim to have
done it after Black Sabbath.
the ideas were out there in various forms, but Sabbath crystallized them into a unique,
instantly recognizable genre, making them the first undeniable heavy metal band, and
since metal was how I got into music in the first place, I figured it was time to pay
tribute by looking at one of my favorite Sabbath songs, Iron Man.
let's take it apart.
(tick, tick, tick, tick, tock)
the song starts with Bill Ward playing slow quarter notes on the kick drum, like footsteps
from an approaching monster: (bang) and then suddenly Tony Iommi comes screaming in with
these powerful bends: (bang) like the wordless scream of their metallic man.
these two parts, combined with a robotic voice proclaiming itself Iron Man, immediately put
you in the middle of a monster movie, like you're hiding under a table as Iron Man approaches.
it's a really nice piece of soundpainting, using musical elements not for their tonal
functions but for the imagery they create.
from there we move into the song proper, beginning with the iconic riff: (bang) and I'm gonna
do something a little unusual: I'm gonna analyze this in two different keys.
now, don't get me wrong, I'm pretty sure the song is best understood in the key of E minor,
but there's some parts of that make more sense if you're willing to think of it in B minor
too.
it's kinda like a ghost key, a faint echo of tonality sitting behind the main key and
providing additional elements.
like, take this trill: (bang) now, sure, both these notes are in E minor, but metal, especially
early metal, draws heavily from the blues, so I wouldn't actually expect to see the E
minor scale.
you're much more likely to see minor pentatonic, which is where you take minor (bang) and remove
the two least important notes: (bang) to create a more streamlined scale that's less internally
dissonant, and here's the thing: F# and G, the two notes in this trill, are also the
only difference between E minor pentatonic and B minor pentatonic, so we can kind of
view the trill as representing two different notes in our two different keys.
in the main key, E minor, it's a G, and the riff sounds like this: (bang) we're basically
just outlining an E minor 7 chord. if we ignore the first half of each bar, though, we notice
that they both end the same way, with D resolving to E. (bang) this repeated resolution is one
of the main reasons I think the E analysis is stronger: it's really hard to not hear
this as b7 going to 1, and approaching it from below in the first bar and above in the
second makes it even harder.
the shape of the riff is effectively orbiting around this central resolution, but it is
a little weird that we're not starting on the root. in fact, if we look ahead we see
most of the riffs in this song actually start on B, not E, so let's at least consider the
possibility we're in that key.
here, that trill becomes an F#: (bang) and we instead see the development of a chord
progression, from I to IV to V and back to IV. this sort of motion is common in early
rock and other blues-based traditions, where instead of pointing back to I, the V chord
just melts down to IV, which then resolves back home.
the D resolutions do kinda interfere with this, since they're not really a part of that
implied progression, so again, I don't think we're actually in B, it's just sort of lending
its F# to us for flavor 'cause if we just play Gs there, the whole thing sounds kinda
flat.
this section is also doing something cool with textures: not only is Iommi playing this
riff, but Geezer Butler is doubling it on the bass, and once Ozzy Osbourne comes in,
he sings it too.
every melodic part is playing the exact same line in unison, creating a texture called
monophony, or one sound.
(bang) this sort of collective monophony, where multiple voices perform the same line,
is common in religious chants, and using it here gives the story of Iron Man a sort of
mythic quality, a singular musical focus that draws you in from all sides.
from there we move to the interlude: (bang) where we get a new riff, and this is where
I think the ghost key analysis starts to really pay off.
we seem to be outlining a pair of chords, first B minor, then some sort of A chord.
in E, these would be the V and IV, and again, that's a pretty common blues thing.
if you're familiar with the 12-bar blues pattern, these are bars 9 and 10, and we're just looping
them a couple times, but that feels a bit off to me 'cause in the 12-bar blues, bar
9 feels like an event.
there a big jump up to the V chord, suddenly throwing you somewhere completely different,
but in Iron Man that's just not what this feels like to me.
it feels very smooth, and I think that's best explained by the idea that we were already
kind of in B the whole time.
in that key, this section starts on the I chord, which is why it's so stable, and then
it goes to bVII. as we mentioned before, bVII to I is a pretty common resolution in blues-influenced
music too, so this section can easily be read as a vamp on those two chords. if we take
a broader view I'd say it's still V-IV in E minor, but the ghost key's gotten a bit
stronger here.
but enough about keys, what's going on with this G#?
that's not in E minor or B minor.
no, this is what's called an approach note: we're trying to get back to A, so we're just
stepping into it from below, and the cool thing about approach notes is they don't really
have to be in the key.
I mean, they can be, we could've used G natural here: (bang) but half-step motion is generally
stronger than whole-step motion, so using G# instead makes it feel more powerful.
this is especially important because the G# falls on beat 3, one of the most prominent
parts of the bar, and if you're gonna do something weird in such an important position, the best
way to sell it is to really commit. and that half-step motion continues upwards, ending
the bar on a Bb. in fact, both bars end on Bb. as we'll mention in a bit, Bb is kind
of in E minor, so we can read it as belonging to that key, but really I think it's just
a passing note: we're trying to move from B to A and back again, and the only standard
note that fits there is Bb. just like the G#, it's there to smooth out the transition,
and since it's on a much weaker beat it kinda just melts into the background of the riff.
and I want to quickly mention the rhythm in the first bar: Iommi hits the downbeat, and
then switches to upbeats for the rest of it.
this gives it a bouncy, syncopated feel, in contrast to the plodding, almost metronomic
main riff. the second bar goes back to emphasizing the beats, but remember this rhythm, it'll
come up again later.
this is also where our monophony starts to break down: Butler plays the first half along
with Iommi, but under the A chord his line is different: (bang) it's really quiet in
the original track, so it doesn't have a huge impact on the listening experience, although
you can definitely feel that the bass has at least stopped playing in the lower register,
which gives the line some extra lift even if you can't tell exactly what it is doing.
that's probably for the best, 'cause the line actually clashes pretty hard with Iommi's
part in a couple spots: the first A-G trill is played underneath the G#, so you get two
different kinds of half-step rub, and then he falls down to E just as Iommi goes to Bb,
making a tritone. if these parts were both equally loud they'd sound really dissonant
together, but because Butler's is so much quieter you can hear the guitar as the lead
and the bass as a set of decorations underneath.
it all works because the mix tells you how to treat each part.
although, honestly, if the bass just laid out here instead, I'm not sure it would've
made much difference.
still, though, fun little easter egg.
before we move on, though, I want to talk about another part that's doing a whole lot
more here: the drums. at the same time Butler jumps up for that high part, Ward lays down
a huge drum fill: (bang) that really brings the section to life.
it's easy to forget the drums because they're not playing notes or chords, but in metal
especially it's hard to overstate the importance of a good drummer, and this section shows
why.
again, the verse has this slow, plodding quality to it, and the interlude largely does too,
but thanks to Ward's drum fills, it takes on a whole new sort of energy.
and the homophony continues to break down once we get to the chorus.
here, Iommi holds chords while Butler takes over the riffing: (bang) walking up and down
the various chord scales to provide some motion while Iommi takes a bit of a break.
here, we see that same I-bVII vamp, but this time in our main key.
we've taken our ghost progression and brought it home.
we also get a bit more information on the implied chord qualities: Iommi's playing power
chords, so he's no help, but over the E chord, Ozzy sings a G and Butler plays a D, so all
together this is E minor 7, and then for the D chord they both play F#s and Butler adds
a C# too, so it's D major 7.
that's a bit strange: in E minor, the D chord is supposed to be dominant, with a C natural.
I mean, I supposed we could be in E dorian, a scale that's like minor but with a raised
6th, making it less dark and more happy, but that doesn't sound like an accurate description
of Iron Man.
no, I think this is best viewed as a call-back to that G# in the interlude: we're borrowing
the chord progression from our ghost key there, so why not borrow the approach note too?
in the second half of the chorus, our progression gets interrupted by a new riff: (bang) and
I've got a bit of a confession to make: I said that in this sort of blues-influenced
music we'd expect to see the minor pentatonic scale, but that's not actually true.
what we'd really expect to see is the blues scale, which is like minor pentatonic but
you add an extra note in between the fourth and the fifth: (bang) giving you this cool
little run of half-steps inside your otherwise open scale.
with that in mind, let's go back to the riff. we start with a couple B power chords to define
the harmony, then we have these little 16th-note walk-ups. the first one is B, D, and E, which
you might recognize as the first three notes of our main riff, just played a whole lot
faster, like a little motif to help tie the sections together.
from there, we see the real reason I wanted to do this whole ghost key thing in the first
place: Iommi plays the half-step clusters from both B blues (bang) and E blues (bang)
back to back.
if this whole thing is in E, then we'd probably have to just call this F a random passing
note, but given the structural significance of this cluster in the B blues scale, I think
that's a much weaker analysis, especially because the line starts by making sure you
know that the implied harmony here is a B chord. this riff is effectively the synthesis
of our two keys, clearly cementing us not in either one, but in both at the same time.
and that has interesting implications for the harmony, too.
we said the first two chords were I and bVII, which they are, but they're also kinda IV
and bIII. they have this downward momentum that lands on the B chord, but then that B
chord turns around and points us back toward E. listening to this section, I can easily
convince myself to hear either chord as the point of resolution.
after the second chorus, though, everything changes.
(bang) here, we've shifted to a whole new key, C# minor.
it's honestly a little surprising how smooth this transition is: C# minor isn't all that
similar to either of our previous keys, so you'd expect at least a bit of a jolt, but
they cover it up really well with the shape of the line: the riff beforehand was walking
up to B, and this one starts on C#, the next note up in that scale, then walks back down.
it feels like a direct melodic answer to the previous riff, and since the notes B and C#
both exist in both keys, they can serve as a bit of a pivot so that by the time we start
resolving to C# instead, it doesn't feel that surprising.
and that resolution may sound familiar: it's the same b7-1 motion we saw in the main riff.
in fact, it's even the same rhythm, just played twice as fast.
once again, motifs.
beyond that, the riff is basically just a walk down the blues scale, but it still feels
super powerful because of the rhythm.
they're playing these sharp staccato stabs on all the upbeats, just like we saw in the
interlude riff but using 16th note syncopation instead of 8th notes, and the whole thing's
done in stop time, where everyone is hitting those same attacks and nothing else.
combining syncopation, staccato, and stop time turns each individual note into its own
musical event, so you really feel the pull of this descent.
from there we launch into the solo, which is in double time.
(bang) this sudden jump in tempo, combined with the key change, makes the solo feel almost
like an action sequence to me: the song has introduced us to the monstrous Iron Man through
the verses and choruses, and now he's finally ready to attack.
it's a very cinematic approach to songwriting.
notewise, the solo seems to stick almost exclusively to the C# minor pentatonic scale, and since
all the notes in that scale sound good together, this means he can do basically whatever he
wants and it'll work.
it also gives Butler the freedom to play around: he's mostly playing C# in various octaves,
but he also throws in some runs like this (bang) and while they may have coordinated
this beforehand, they kinda didn't have to, because whatever notes Iommi was playing over
it, as long as they mostly stuck to minor pentatonic, nothing was gonna clash.
it almost feels like they're both soloing at the same time, and they're able to get
away with it thanks to the power of pentatonics.
after the solo, we get that C# walk-down again, then the chorus riff, then back for one final
verse. after our whirlwind tour of all the riffs we've heard so far in the song, everyone
drops out while Ward switches back to double time and starts building up energy again.
(bang) Butler joins him, playing E really fast, and then finally Iommi comes back with
those wordless guitar screams from the intro.
back then, these were played over a slow, plodding kick, but this time they're over
some of the busiest rhythms we've heard all song.
it's incredibly frantic, conjuring up an image of all the people running away from Iron Man
now that his rampage has truly begun.
after a while, Butler starts playing roots to a chord progression while Iommi gives us
one final solo, although interestingly the two don't seem to have much to do with each
other.
Iommi's sticking pretty strictly to E minor pentatonic, whereas Butler's doing this descending
half-step line that goes outside the scale.
(bang) the two even directly clash sometimes, like when Iommi plays a D over Butler's C#:
(bang) but because the pentatonic scale is such a strong sound, and because we've already
heard Butler's loop a couple times at this point, we can independently accept each component
even though, on paper, you might not expect it to work nearly as well as it does.
and that's pretty much it.
I think this song is a great example of how much storytelling you can do with musical
structure: it honestly plays almost like a movie, with clear narrative beats driven by
their compositional choices.
plus it's got some amazing riffs, all built from pretty simple components but perfectly
crafted to make it feel epic from start to finish.
songs like Iron Man helped define a new path for increasingly heavy music that eventually
led to some of my favorite artists of all time, and 50 years later, it still rocks just
as hard as the day it was released.
anyway, thanks for watching.
as always, this song was chosen by my patrons on Patreon: the poll to pick the next one
goes up over there next week.
you can also join our mailing list to find out about new episodes, like, share, comment,
subscribe, and above all, keep on rockin'.