How this is different from other music theory

This page is for readers who already have some theory background and want to know how this site's approach is different from what they learned.

Different from what? The two big pedagogies are common-practice-period ("classical") theory and jazz theory. There's also what I call beginner theory, which is my shorthand for patterns I've seen across books and videos trying to teach learners who are starting from nothing.

Here's the short version:

Classical music pedagogy organizes harmony around Ionian / Aeolian functional grammar and Romantic-era techniques
Jazz pedagogy centers the same functional grammar and adds per-chord scale choice for improvisers
This site organizes its material around modal environments, how songs move through them, and how songs move between them while keeping a fixed root. There are six core modes instead of two, which reflects the breadth of practice in popular music.

The rest of this page is the detailed argument, broken down by pedagogy.

If you're starting from zero: you can probably skip this page (start with the Getting ready for the mode lessons instead). But if you do have some background, this should help you understand the approach of the rest of the site. A lot of the choices I made while building its framework were in response to the problems I experienced with the standard music theory approaches, and it'll help to know exactly where it's positioned relative to what you already know.

Versus the rotational view of modes

Beginner theory, the kind you see on YouTube or in "music theory for dummies"-type books at the bookstore, focuses on the major and the minor scale (a.k.a. the natural minor scale), which this site calls Ionian and Aeolian, respectively (beginner books usually list three minor scales — though see the section below on why I think that's misleading).

A book like this might ask you to get familiar with some chords and a couple common progressions, though this is usually heavily weighted toward Ionian's progressions. Later, modes will be introduced as rotations of the major scale: "Dorian is just the major scale starting on the 2nd scale degree", "Mixolydian is the 5th mode of the major scale", etc. For someone learning to hear and use modal harmony, this is the wrong foundational view of what modes are. It trains you to treat Dorian, Mixolydian, etc. as things that exist inside the major scale, rather than as independent environments with their own harmonic lives.

(Even people who didn't learn modes as rotations still inherit this baggage through the "X is the Nth mode of the major scale" terminology.)

The "rotation" frame only tells you how to spell these modes; it does not tell you how to inhabit them. It does not put you in a position to actually understand what each mode feels like and how each tends to behave in popular music. It's also just incomplete: many common modes (most importantly Phrygian Dominant) aren't rotations of the major scale at all. In fact it's common for beginner material to claim that there are 7 modes in music, which undersells the practical modal universe considerably; what's true is that there are 7 in the major scale's family — its rotations — but there are several other families songs use modes from.

Parallel comparison

My framework says that parallel comparison is a much better starting point. That is: compare modes built on the same root. Want to hear what Phrygian sounds like? One way is to start in C minor (Aeolian) and change the D to a D♭ (i.e. lower the 2 to a ♭2) to get C Phrygian. Some beginner material does teach the parallel perspective — e.g., "Dorian is a minor scale with a ♮6" — which is a good-enough way to bootstrap someone's understanding: it keeps the same root and gets you to listen in terms of alterations — what scale degrees can you raise or lower by a half-step, and what exactly does each of those choices do to the sound palette? But even then, it still doesn't tell you much about how a mode works as an environment.

Parallel comparison gives you a much better handle on learning modes as environments, for two basic reasons:

Each mode has its own unique internal structure, which is obscured if you're thinking of it as a region of a major scale. On this site, we start from the scale formula and dive into the mode itself: its native chords, characteristic pulls, common vamps and turnarounds, and so on.
You need this perspective to understand modal interchange, i.e. interacting with neighboring environments.

A modal interchange example, to illustrate. Commonly, rock and blues will use Dorian layered over Mixolydian — that is, the tune might be in C Mixolydian at its core, but frequently borrow a ♭3 (E♭) from C Dorian (see the lesson page on this for some examples). Same root. If you try to describe this from a rotational perspective, you'd say:

C Mixolydian is the 5th mode of F major
C Dorian is the 2nd mode of B♭ major
Therefore in a sense you're layering B♭ major over F major

I'm not sure what that's supposed to get you. F major and B♭ major are shortcuts to tell you what notes are involved if you mostly just have major scales memorized. But does it give you any insight about what this modal environment sounds like? No — this environment doesn't sound like F major or B♭ major at all. It sounds like Mixolydian with the third sometimes flat. So it's analytic complexity with no benefit.

A second worked modal interchange example, in the wild: Wikipedia describes the Andalusian Cadence — a four-chord progression that's everywhere, in some form or another — like this:

The Andalusian cadence can be regarded as a modulation between the Phrygian mode of a Major parent scale and the Phrygian Dominant mode of a Harmonic Minor scale, e.g. E, F, G (phrygian) or G ♯ (phrygian dominant), A, B, C, D.

The root in the music Wikipedia is describing here (flamenco music, but I also know Balkan tunes that do this) is E: the E major chord is home, and the A minor chord is the iv. So the progression is iv–♭III–♭II–I, or Am–G–F–E.

First, notice it doesn't say which major or which Harmonic Minor scale, so let's fill those in: if we're talking E Phrygian, then the "parent major" they're referring to is C major (E Phrygian == "3rd mode of C major"), and if we're talking E Phrygian Dominant, the "parent Harmonic Minor" is A Harmonic Minor. So these "parents" don't even have the same root and neither is the root you actually hear.

Second, what your ear hears between that G and G♯ is not modulation — you don't hear an instantaneous key change from C major to A Harmonic Minor. This is just modal interchange, a switch between a ♭3 (E Phrygian) and a ♮3 (E Phrygian Dominant) (see my tutorial on Phrygian Dominant + Phrygian modal interchange). Describing this as "modulation" isn't a random mistake either. The rotational frame itself implies that this is a key change — and it's just not, not even close. The first example above showed that it gives you extra complexity for no benefit, and this example shows that it gives you a wrong answer. The frame's unit of analysis is the parent scale, so any change of notes looks like it's a change of key — there's no way to say "same root, one note altered" — and that's most of what modal interchange is in practice.

And the parent scales themselves are just a convention. There is nothing about the major scale, or for that matter the Harmonic Minor scale, that makes them inherently parents of the other scales in their respective rotations. The major scale wound up as the "default" scale because classical music was built around it (more on this in the section below) and the pedagogies that came afterward inherited that default and described every other mode relative to it. It didn't wind up this way in other traditions (Indian raga theory, Turkish and Arabic makam theory...). The major scale and its rotations are siblings, as are Harmonic Minor and its rotations.

The Wikipedia page actually gives this progression two roots — iv–III–II–I "with respect to the Phrygian mode" (E) or i–♭VII–♭VI–V "with respect to the Aeolian mode" (A) — and the passage I quoted is about the E version, which is a Phrygian / Phrygian Dominant mix progression that I know from Greek and Balkan tunes (Misirlou's B section, for example). On this site, these are two different vamps, because the root is different, even though the chords are the same. The A version is the one that's everywhere in pop and rock, though what most commonly loops there is a 3-chord version: i–♭VII–♭VI. The added V that Wikipedia mentions is one of several ways songs extend it, which I'll address in the Aeolian mode lessons.

Detour: "three minor scales" claim

Here's something that's frequently told to beginners:

There are three minor scales: Harmonic Minor, Melodic Minor, and Natural Minor (a.k.a. Aeolian)

And here's what I see in all the music I've analyzed:

Harmonic Minor is actually shockingly rare as a base mode: very little music is written in it — a whole section with both a ♭6 and ♮7 the entire time. Instead what you hear is Aeolian with a V7 borrowed from Harmonic Minor, which is extremely common. Occasionally you'll hear Phrygian borrow from Harmonic Minor (V7 in this case too) or Ionian borrow from it (♭VImaj7).
Melodic Minor is also pretty rare as a base mode. It's a fairly niche color. But it shows up as a borrowed color. Famously, you can brighten up an Aeolian line by borrowing a ♮6 and ♮7 from Melodic Minor and going 6 → 7 → 1. You'll see the color used in jazz a decent amount, over i6 chords. It's also where the V7 chord comes from in Dorian, which includes Dorian-based minor blues usage.
"Natural Minor" (Aeolian) is the real deal. If there's a single most common base mode in music, it's this one.

What is a minor scale, in general? I think the field plays fast and loose with this term without really defining it, so let me give you my take.

A totally defensible definition is that there is exactly one minor scale: Aeolian. When people say "the minor scale", they mean Aeolian.
You could also say it's Aeolian plus the local neighborhood of modes Aeolian often borrows from.
Another defensible definition is "any scale where the root chord is a minor chord (1 ♭3 5)". But there are a ton of modes that fall under that (roughly sixteen, depending on how exactly you slice things).

If I were to choose three representative modes among those sixteen, I'd pick a different group of three: I'd pick Dorian, Aeolian, and Phrygian. These are the real hubs in the darker side of scale-space.

So, the common claim about "three minor scales" is a fact about how classical music was written, that got passed down in the beginner pedagogy as if it were the whole map of minor key harmony, and it's not — it's both not broad enough and focused on the wrong environments.

And this is a representative example of my experience revisiting beginner pedagogy after doing a couple of years of heavy song analysis: it has a lot of inherited baggage that breaks when it encounters the diversity of actual bodies of music. It's no wonder musicians struggle to apply its teachings to songwriting. This is a core aspect of what this site is trying to correct.

Versus university-level classical music pedagogy

My first exposure to music theory was through the standard American university pedagogy, which by-and-large studies music from what's called the common practice period. If you're in one of these classes, one of the first things they'll teach you is that what people colloquially call "classical music" is actually three different periods: the Baroque era (Bach, Handel, Vivaldi), the Classical era (Haydn, Mozart, early Beethoven), and the Romantic era (Chopin, Wagner, Brahms, Tchaikovsky, and many others), spanning roughly from 1650 to 1900 in Europe. And together these three eras are called the common practice period.

The first critique is about what modes get to be a basic home environment. Classical pedagogy gives you just two: Ionian and Aeolian, and assumes you'll be in one of those two modes essentially at all times. Popular music has six, with a large list of others showing up as borrowed colors.

Why is this? Why these two? Mostly because of functional harmony: a family of chord-motion paths built around a V7 chord pulling you to the root chord. The central idioms are ii–V–I in Ionian and ii7♭5–V7–i in Aeolian (with the V7 borrowed from Harmonic Minor), with a large field of substitutions and expansions on top.

Many idioms in harmony have expected next moves — for example, if you vamp I–♭VII–IV in Mixolydian, your ear will develop an expectation pretty quick — but functional paths are different in degree, in two ways. First: they're the strongest pulls in harmony. A V7 "wants" to go somewhere, and there are several ways to satisfy it — going up a fourth to the root chord is the strongest, most complete resolution, but a half-step up (V7–♭VImaj7 in a minor key, for example) also sounds great, and releases some of the tension. Second: functional paths chain on a level no other chord progression idiom comes close to. Ionian's ii–V–I for example can get expanded into iii–vi–ii–V–I, so you can get pretty far from home and ride it all the way back in, or take a detour or two along the way. That's why my metaphor for functional paths is railroads: tracks you can jump on and off to help you land somewhere in a legible and satisfying way, most often back to the root chord at the end of a phrase.

Much of the repertoire's larger-scale motion patterns involve those same rails re-laid onto a temporary new root — secondary dominants, tonicizations, modulations — which come easily in this style because the new key is almost always another Ionian or Aeolian.

Ionian and Aeolian are where the strongest rails live. The other core modes have some functional idioms of their own, but they're each a little strange and a lot weaker; what usually happens is that a song borrows a turnaround from Ionian or Aeolian when it needs it (see the "V7 as a turnaround" section in my Mixolydian lesson for "interchange with Ionian").

And the common-practice repertoire rides those rails hard. Pieces rarely loop on a vamp the way popular music does; instead, the harmony keeps moving, with longer progressions and nearly continuous functional motion. Play a passage from a Mozart piano sonata, and then start playing a Mixolydian vamp: it will stop sounding like classical music. The restricted palette is part of the sound of the tradition.

Popular music uses those same rails. Ionian and Aeolian are everywhere, in every genre, but other genres aren't attached to their functional grammar anywhere near as much. Dorian, Mixolydian, Phrygian, and Phrygian Dominant are also common home environments, and there are maybe ten others you'll hear occasionally as a home — plus another ten or so that only ever show up as borrowed color. Functional motion tends to cluster at the end of phrases. The rest of the time a song might be vamping, making some other move, or chaining several kinds of motion into a longer progression — with the rails being one of the things in that chain.

So, the classical pedagogy's focus on Ionian and Aeolian is right for its repertoire, but it makes every other mode look like a deviation rather than an environment with its own identity, and that doesn't generalize.

The second critique is about modal interchange: how borrowed colors get described.

Romantic-era music especially can get really bold and move dramatically to other keys and modal colors, but those excursions are usually heard against major or minor key homes that ground the piece and that composers can re-establish strongly.

The pedagogy has sophisticated ways to describe that colorful material: secondary dominants, augmented-sixth chords, chromatic mediants, altered dominants, key changes, and so forth. My objection is that harmonic color is organized by technique and expansions of Ionian/Aeolian grammar, rather than by location in modal space. That makes sense for common practice period repertoire, because the music itself is primarily organized around that Ionian/Aeolian grammar. But these concepts don't, by themselves, teach you to hear Dorian, Mixolydian, or any other mode as an environment with its own characteristic motions and vocabulary. They're the wrong organizing layer; they're not what you want to prioritize in a general purpose music theory. (I think a modal perspective can add useful detail even to Romantic-era harmony, but that's a deeper topic than I can get into here.)

For popular harmony, I think studying modal environments should come first. Secondary dominants and chromatic mediants in particular can be introduced with the particular modal environments in which they're actually heard and used, rather than as free-floating techniques whose color is just described as "chromatic" (using notes outside the mode, generally). And the rest of the techniques taught in university pedagogy are best learned after modal ear-training.

Versus jazz harmony pedagogy

Jazz theory contributes some powerful conceptual machinery, in particular its chord-scale theory. Chord-scale theory treats each chord as a local note-choice problem: given a chord symbol, what scale contains its chord tones and idiomatic tension notes? I don't have an objection to this system — I use it myself as a jazz improviser — but it answers a different question than the modal analysis this site is teaching. Chord-scale theory asks you "what can I play over this chord right now?". Environmental modal analysis asks, "where are we? and what does this chord mean relative to the home environment of the song?"

Let me break down a common jazz idiom to illustrate: a ii–V–I ("two five one") turnaround. In C major (a.k.a. C Ionian), this would look like:

Dm7 - G7 - Cmaj7

Chord-scale theory says:

Play D Dorian over Dm7
Play G Mixolydian over G7
Play C major over Cmaj7

All three of these scales have exactly the same notes: they're rotations of C major. But during this passage, the music doesn't actually inhabit three different modal environments. It's all in C Ionian, and this is part of Ionian's characteristic chord-motion grammar.

Jazz needs this kind of shorthand. Chord-scale theory is meant for improvisers — the jazz tradition is largely about players jamming together on tunes they may not know intimately, and a lot of these tunes are pretty harmonically dense. Players need to orient themselves to a chart quickly (often in real time, while they're playing it), and doing a full modal analysis of every modal color and transition would take way too long.

With enough practice, those chord-scale labels become embodied knowledge of a tune's color profile, energetic shifts, and voice-leading paths. So jazz players don't actually need modal analysis in order to understand a chart deeply. But chord-scale assignments don't directly encode the song's large-scale harmonic structure.

Jazz harmony does sometimes teach modal analysis. One of my first serious introductions to the topic was in the "Minor Key Harmony" chapter of The Berklee Book of Jazz Harmony, where it framed minor key harmony as a mix between five parallel modes: Aeolian, Dorian, Phrygian, Harmonic Minor, and Melodic Minor. That approach works well for a lot of tunes with a more-or-less stable minor home key, like "St. James Infirmary".

There's also "modal jazz", but that's its own subgenre, not just "jazz that mostly sticks to one mode". "Summertime" for instance primarily lives in Aeolian, Melodic Minor, and Harmonic Minor (i.e. it sticks to Aeolian and some common borrowed colors), but it doesn't follow some of the other idioms of modal jazz. Modal jazz tends to marinate in modal environments — long spans sitting on a single chord, slow harmonic movement, or extended vamps; frequent ii–V–I turnarounds aren't the main engine of harmonic movement here. Environmental modal analysis is (maybe unsurprisingly) well-suited to this genre.

But a lot of the standard jazz repertoire doesn't work like that; instead, tunes move rapidly among different major and minor key centers, which most often looks like chaining ii–V–I progressions through keys that only last a few measures. If you're a jazz player, think of “Solar”, “Body and Soul”, or “On Green Dolphin Street”. Chord-scale theory is immensely helpful real-time shorthand for this. A full modal description can become unwieldy if every new key is named relative to the tune's original root. In "All The Things You Are", for example, there's an iconic abrupt key change from A♭ major to C major, which would be "A♭ Lydian Augmented ♯2 ♯1" in fixed-root terms. That name tells you about the dramatic brightening that happens there, but it doesn't match what the C major phrase feels like from the inside — it feels like an ordinary Ionian key! Just not the one you started with — and it only lasts three bars.

So, there's a kind of contradiction: chord-scale analysis might constantly invoke locally-scoped Dorian and Mixolydian scales, but the large-scale structure of the song is still an Ionian or Aeolian key center.

Here's the thing about that harmonically dense repertoire, with its temporary key centers and rapid chains of ii–V–I's: this is the language of a specific harmonic tradition within jazz. It's not how harmony works, by default, in other genres. In a metal or dance-pop song, many of your chords will usually belong to the same modal environment (often just one environment for a whole section, or even the whole song). And so assigning chord-scales to every chord would just be re-describing that same mode over and over; it would be extra labelling that doesn't come with extra understanding. For most genres, the better default method is to study what the music does within each modal environment, and where it moves from one environment to another.

modalinterchange.com's approach

With the critiques above in mind, here's what this site is putting forward:

Six core environments rather than two. Ionian, Mixolydian, Dorian, Aeolian, Phrygian, and Phrygian Dominant. They each get studied on their own terms: native chords, characteristic vamps and turnarounds — and importantly, not as rotations or derivations of the major scale.
Borrowed colors are named by where they come from. So: secondary dominants, altered dominants, chromatic mediants — the primary question we ask is "which neighboring environment does this come from?", not just "what is the name of this technique?".
Chord-scale theory is still a good tool for jazz improv. This site approaches harmony from a level above it though — "what mode are we in, and where is this chord relative to the root chord?". It's compatible with chord-scale theory and I use both approaches when I play jazz.

This site organizes its material around modal environments and modal interchange: the ways music moves between environments built on the same root note. It's designed first for popular music traditions whose default harmonic behavior is to keep the same root note for substantial spans of time — that is, to move within one modal environment or between parallel environments built on the same root. In these traditions, frequent travel among temporary key centers is the exception, whereas in much of the standard jazz repertoire (and to a lesser degree, the common-practice-period repertoire), that's part of the basic grammar. This site focuses on the recurring paths musicians use through and between modal environments instead, and it teaches that vocabulary with the goal of improving one's ability to both recognize and create music in your own genre.

Where this framework came from

The jazz and classical pedagogies are my background — they're what I learned from — and I try to reuse their terms, frames, and systems wherever I think they work well. But playing in bands in my 20s, it bothered me how little the music theory I learned in college helped me understand the charts I was playing. There was a big, mysterious gap (and I was good at my music theory classes!), which I now understand to be: at a fundamental level, I couldn't describe what I was hearing.

And my experience wasn't an outlier. Most other adult musicians I played with didn't study this material or didn't want to. They would find it confusing, intimidating, unnecessary, or — like me — they'd have learned some theory, and found it less useful in practice than they'd hoped.

That frustration pushed me to explore another direction: a systematic study of modes and modal interchange. Along the way, I kept coming back to some fundamental questions, to see if I could come up with some real answers.

Why do the normal pedagogies have such a spotty uptake record with experienced musicians? Because they don't prioritize teaching you to hear and recognize the bulk of the harmony used in popular music. That's what most of the page above is getting at.

Why are there so many great musicians who don't see themselves as understanding theory? (In fact, why are there so many amateur musicians who make compelling music with just their ear as guidance?) Compelling chord motion is something you can feel. You don't need it all mapped out in your head before you can find something you like (mapping just helps a lot). Lots of beginners expect theory and rules to tell them what chord progressions "sound good", and this is misguided, because a TON of things sound good. Harmonic ear-training should teach you what's possible; you're still relying on your intuition to work out what you want.

Why do music teachers consistently tell students things like "you have to know the rules in order to break them"? The "rules" are mostly about functional grammar; a lot of what's called "breaking them" is just playing the grammar of a different mode or a different style. Additionally: a lot of the rules are about voice-leading, which is not really the focus of this framework; but my answer to that is that the rules describe idiomatic voice-leading for classical and jazz ensembles, i.e. how to make the texture sound like it belongs in that style. Voice-leading idioms for rock, for example, "break" these rules (parallel fifth motion is the main way), but that's part of why the songs sound like rock.

This framework's bet is that there's a third way. It's already how a lot of musicians think about music, more or less. It's just not synthesized into one place, and there are parts missing. I've heard fragments of modal theory from jazz books, teachers, YouTube videos — and frankly, I think a lot of this theory is found implicitly in how popular songs are written. The closest prior attempt I've found is the musicologist Philip Tagg's book Everyday Tonality, which covers a lot of this ground as academic work, whereas this site is trying to present it as a course and a reference. My approach differs from Tagg's in many of the details.

My site is an attempt to put it all in one place and fill in the gaps. The material is still in development, but start with my lesson on the Dorian i7–IV7 vamp and see what you think.