hey, welcome to 12tone! today I want to do something a little bit different and talk
a bit about how I, personally, think about music.
I'm a huge fan of structures, so I thought I'd delve into some of my mental models on
one of the most nebulous topics in theory: modality.
this word gets used to describe a lot of different but related ideas, but in the broadest possible
terms, it's basically the overall structure of a scale.
for instance, is this scale (bang) more like this one (bang) or this one?
(bang) I think most people would say the former, but in both cases we've just changed one note,
so… why?
well, the version they teach you in theory 1 goes something like this: the 3rd degree
of the scale is the primary modal note, and its quality tells you the modality of the
scale.
if it's a major 3rd you've got a major scale, and if it's minor… well, you can probably
figure it out.
this is sometimes combined with the 6th, which is the secondary modal note, although they
don't tend to tell you what happens when the two notes disagree.
but that's a little bit too simple for my tastes, so I've developed what I like to call
the Triforce of Modality.
quick caveat: I'm not claiming that any of this is my original work.
I've never seen it put together in exactly this way, but all the parts of it are pretty
well-known in the theory world.
also, I'm gonna be focusing on traditional 7-note scales.
the model works on others, but it takes some adapting and I just want to get the basic
ideas across.
anyway, this model can work either as an analytical tool, to break down a scale you've already
got, or as a generative tool.
each part contains a set of building blocks you can use to put together scales you might
never have considered, and they're pretty handy for exploring the possibility space
if you find yourself getting bored with the normal options.
the first method is what I like to call melodic modality.
this is what you'd expect to find by walking up and down the scale, and it can be represented
by a series of steps.
for instance, any theory student can tell you that the major scale is built by picking
a root, then going up a whole step, then another whole step, then a half step, then whole,
whole, whole, and finally half.
this pattern is literally burned into my brain, and it serves as a good introduction to this
idea.
by default, a 7-note scale has five whole steps and two half-steps, and the way those
are arranged is the core of melodic modality.
the whole steps don't really do that much: they sound pretty neutral, and also there's
just a lot of them.
they're mainly filling the gaps between the half-steps, which sound a lot more distinctive,
and really control the identity of the scale.
this is partly based on their positions above the root, but I think more important is their
positions relative to each other.
in the major scale, they're about as spaced-out as you can get: they've got two whole steps
between them on one side and three on the other.
this spreads out their dissonance and mellows the scale a bit. if we move them closer together,
we might get something like this (bang) where we see this little cluster in the middle,
creating a bit more confusion.
but, of course, not all scales are that straightforward. for instance, harmonic minor (bang) has an
augmented second between two of its scale degrees.
it gets away with this by also adding in a third half step, leaving us with just three
whole steps and giving the scale a really complex sound.
you could even make a scale with two augmented seconds (bang) or even a double-augmented
second (bang) as long as you compensate for the added distance by shrinking some of your
other steps to match.
I like to think of this process as mutation, and the further you've mutated from the initial
5-2 set-up, the more alien it's likely to sound.
you can even mutate up a scale with no whole steps at all (bang) if you want something
that sounds really, really weird.
next up is harmonic modality.
this, as the name implies, is based on the harmony.
specifically, it's based on what are called primary triads: that is, the most important
chords in the scale.
traditionally, these are the I chord, the IV chord, and the V chord, and if you know
the qualities of all three, you can generate the entire scale.
check this out.
we start with a root. this is just a fixed, arbitrary point, so let's go with A. the root
of the scale is also the root of our I chord, so if we know our I chord is major, that tells
us what the other chord tones are: C#, the 3rd, and E, the 5th. now we've found the root
of our V chord, and if that's major too then we get two new notes, G#, the 7th degree of
the scale, and B, the 2nd. we don't have the root of our IV chord yet, but we can find
it: the construction of the IV chord contains the root of the scale, and since we know what
that is, we can just work backwards from that to find the last two notes.
if our IV chord is also major, that gives us F#, the 6th degree, and D, the 4th, and
voila. we have the entire A major scale.
and you can do this with any set of chords you want.
let's say you wanted to build natural minor: that's I minor, IV minor, V minor.
how about harmonic minor?
that's I minor, IV minor, V major.
you can even add in weirder chord qualities: if we take I diminished, IV minor, and V augmented,
we get this (bang) which is called Locrian natural 9. we could even use I minor, V major,
and IV sus 4, which gives us this scale (bang) which, looking it up, appears to be an Indian
Carnatic Raga called Varunapriya although, of course, directly comparing Western scales
to Indian Ragas is dangerous to say the least.
harmonic modality, by the way, is where I think the idea of the 3rd and 6th as modal
notes comes from: those notes define the qualities of the I and IV chords, respectively, and
since the V chord is traditionally always major, those two were the ones that changed
between major and minor keys. this approach is a little more rigorous than melodic modality,
because it's literally just picking three chord qualities and seeing what spills out
and, again, it's a great way to find scales you might never have considered.
I mean, I'd never seen Varunapriya before making this video.
anyway, the last method is what I call chord scale modality, which looks at how the notes
of the scale relate to its underlying harmony.
this approach breaks the notes into two groups.
the first is the chord tones, which are the notes that are part of the scale's harmonic
identity.
traditionally this is the root, 3rd, 5th, and 7th, although some scales break that.
these give the scale its overall quality: if they create a major 7 chord, for instance,
you've got a major scale, if they make a dominant 7th it's a dominant scale, and so on.
the other group is the tensions, short for chord extensions, which comprise the rest
of the notes.
these are traditionally the 2nd, 4th, and 6th degrees, although to differentiate them
from the chord tones they're often called the 9th, 11th, and 13th instead, for reasons
that aren't really worth diving into since this video's already getting pretty long.
these give the scale its specific color and, again, this largely comes down to half-steps.
here, what matters is how far away the tensions are from the nearest chord tones. this gets
a bit fuzzy, but a good rule of thumb is that tensions a half step above a chord tone sound
the harshest and should generally be avoided, tensions a half step below a chord tone sound
a little rough and should be used with caution, and tensions at least a whole step away from
both sides sound relaxed and can be used freely.
plus there's some extra dissonance if your tension is a tritone away from a chord tone.
for construction purposes, I tend to refer to the tensions by comparison to the modes,
which if you're not familiar, we've talked about in previous videos. for instance, if
we took a major 7 chord and added in the tensions from the phrygian mode we'd wind up with Phrygian
Major (bang), while combining a dominant 7th chord with the tensions from lydian gives
us Lydian Dominant.
(bang) to build your own scale like this, all you have to do is pick a 7th chord and
then place the tensions next to them in order to create your desired level of dissonance.
so yeah, whether you think of the major scale like this, this, or this, that's a glimpse
into how I look at modality.
I'm sure y'all have your own thoughts on the subject, so please, let me know in the comments.
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