Modes — Richard Bruner Music

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Music Theory Guides

How to Think About Modes

by Richard Bruner

I made the first version of this guide for a friend I was informally tutoring in 2022 before I started my master’s program at California State University, Northridge. He had taken some music theory classes and we were talking about theory one day when the topic of modes came up. I also used that version of the guide as the basis for my teaching demonstration in CSUN’s Teaching Music in Higher Education class in the fall of 2023. This version of the guide has been expanded from the original, and will be further developed over time.

I’ve heard from other people over the years, both directly and from reading comments online, that many people seem to find the idea of modes confusing. I think the confusion comes both from being unclear what modes actually are, and also from the fact that there are several common modes and they have “scary” names (mostly based on various Greek islands or tribes), which look complicated to us Americans today. I always thought that made them sound interesting and I was excited to learn more about them when the topic came up in my classes. So let’s start with a basic understanding of what modes are, and then I’ll show two ways of thinking about them - one that is the most common way, and then one I like better.

What is a Mode?

So what is a mode? The word “mode” in music theory refers to the way a scale is set up. If we go back to the way we usually talk about major and minor scales, we say that they are patterns of half-steps and whole-steps (generally, with the occasional augmented 2nd thrown in). If you start on any given note, and then you play a particular sequence of half and whole-steps, you will get a major scale based on that note (that sequence is W-W-H-W-W-W-H [W=Whole-step, H=Half-step). Minor scales have their own patterns. In older harmony textbooks, you will often see references to the “major mode” or the “minor mode(s)”, and this is where we get into talking about the differences between parallel major and minor keys (starting on the same note - C Major vs. C Minor, etc).

These days, when we talk about modes, we are more often talking about the seven “church modes”, and you can move beyond them to modes on other scales too. When you learn about the “relative major / minor” scales (the major and minor scale that share a key signature), one way they talk about them is to say “start with a major scale and then go two steps down from that starting pitch to get its relative minor” (or two steps up from minor to get relative major). This takes you from C down two (B, A) so A minor is the relative minor to C Major. If you start on G, then it’s ([G] F# E) so E minor is the relative minor, etc. We can expand upon that concept to derive other scales as well, and this is where the church modes come into play. We start with a major scale and then keeping the same pitches (the same key signature) we start on various other notes to derive each of the modes in turn. This is how it’s most often taught to begin with, and that leads us to the first way of thinking about modes.

White Key Method

Here is the most common way of introducing modes. The idea is that if you play only the white keys (natural notes) on a keyboard and start on each note in turn, you will create the seven "church modes". (Note that this is also just based on any major scale as mentioned above, the white keys of the piano are just an easy way to see this). This is true, and is one way to derive the modes, but may not be the most effective way to think about using the modes. This is what you get if you do this:

Brightest to Darkest Modes

This is my preferred way to think about the modes. I call it the "Brightest to Darkest Modes" method. The idea here is that starting on one note there are three "major-ish" modes, three "minor-ish" modes and one odd one out. "Major-ish" vs. "Minor-ish" is determined by the major or minor 3rd degree, and then each mode either is major or natural minor, or is one raised or lowered half-step away. Raising a note makes the scale sound brighter, lowering a note makes it darker, and major is brighter than minor. Here's the resulting order using a starting note of C (red indicates a lowered pitch relative to major or natural minor, green indicates a raised pitch):

Locrian mode is the odd one out because it lowers two scale degrees, and one of them is the 5th scale degree, which causes the i chord to be diminished. This is unusual and difficult to work with because the i chord is normally the most stable chord and diminished chords are unstable. This mode can be used but it will usually have an unsettled feeling and is best when that is the desired context (in that context it can be excellent, i.e. certain dramatic contexts in film scoring or anywhere else that is the intended effect). Other modes either have a major or minor I (or i) chord and melodically work more or less like major and minor scales with a bit different of an emotional feeling. The benefit of this method from a composer's perspective is that you can control the mood of the piece by thinking about how bright or dark you want the piece to be and picking the mode accordingly.

One thing to notice with this sequence of modes is that each time we go from one to the next, we lower one note compared to the mode before it. When we get to Locrian, the only note we haven’t yet lowered is the first scale degree, so if we then lower that note, we wind up in Lydian starting a half-step lower. So you could in principal play through this sequence of modes, lowering one note each time, and then play down the entire keyboard from top to bottom. It would take a very long time to do it, and I don’t think there’s much point in doing it across the whole keyboard, but I do think it would be useful to practice this exercise a few times (maybe even on every possible starting note in one octave) to get comfortable with the patterns involved.

The other thing to keep in mind with modes is that they are the conceptual equivalent of major and minor scales. They are simply patterns of half steps and whole steps and can be applied to any starting pitch, as mentioned at the top of this guide. The issue with the "white keys" method of teaching modes is that it can be easy for students to get hung up on "D" dorian and "E" phrygian, etc. and wind up thinking there is some connection between D and dorian, or F and lydian. But just as it wouldn't make sense to talk about how major is specifically related to Bb and not Gb, there is no necessary connection between D and dorian, or G and mixolydian - they just happen to be the starting notes for those modes if you stick to the white keys on a keyboard. Bb mixolydian makes total sense. Here's how to make it:

Mixolydian is "major-ish", so start with Bb major:

Then we are going to lower the 7th scale degree a half-step, so our A natural is going to become Ab, and that will give us Bb Mixolydian:

Another example: E dorian. Dorian is a "minor-ish" mode, so start with E [natural] minor:

Then raise the 6th scale degree by a half-step, so C natural becomes C#:

Using this trick will allow you to rapidly figure out any mode once you become fluent with the differences.

One other thing to notice is that if you look at E Dorian, you’ll notice it has two sharps. The major scale that has two sharps is D Major. If you look at E compared to D, you’ll see that E is the second scale degree of D, and if you go back to the White Key Method, you’ll see that Dorian is the “second” mode.

Look at our Bb example as well - Bb Mixolydian has three flats (remember the Bb at the bottom and top are the same note, so you’d only count it once). The major scale with three flats is Eb major, and Bb is the fifth scale degree of Eb major. Back to the white keys method - Mixolydian is the “fifth” mode.

I don’t think the white keys method is the best way to approach conceptualizing modes, but the order that you get from that method can still be used for calculating modes from the number of sharps or flats. I use this in a practical sense when I play the tin whistle, as this is how I figure out which key of tin whistle I need to play a tune in any particular mode (tin whistles are basically diatonic instruments, so I have them in most of the keys).

[Update: I’ve been reading the book Musicality by Christopher Sutton and something he mentions in the chapter on Solfa (or Solfege as I call it) clarified a point for me about why I prefer the Brightest to Darkest Method over the White Keys method. In that book, he recommends using “La-based minor” for moveable-do solfege, and the primary reason he gives is that we can think of modes as being based on the different degrees of the major scale. This is essentially the same thing as what I say in the White Keys Method - dorian mode is based on the second scale degree (“re” in solfege), aeolian (natural minor) is based on the sixth scale degree (“la”) etc. So we can start our solfege for our modes from the major key that they are based on, which leads to starting minor solfege on La.

To me, this approach actually defeats the purpose of moveable do in the first place outside of major key music, because it insists on connecting all modes all the time back to the major scale they are based on. Moveable do is better than fixed do solfege in the first place in my opinion because it allows us to connect everything back to the tonic of the key we are in. Using this La-based system is useful if you want to compare a mode to the major scale it’s derived from, but I want the modes to be able to stand by themselves. While Mixolydian can be derived as the fifth mode of major, and there are some ways in which that is useful (tin whistles as mentioned above, or chord scales in jazz harmony, etc), when using mixolydian melodically there is no particular reason why I should have to know that it is the fifth mode of anything. It is its own scale, and fiddle tunes I know in mixolydian do not sound like they are based on the fifth mode of major, but rather on mixolydian, which sounds more like a darker major scale with the b7 scale degree relative to the parallel major (the major scale that starts on the same note as the mixolydian scale, not a fifth below that). Same goes for minor. Minor key pieces (and even more particularly Aeolian mode pieces) do not have to have any direct connection to their relative major. Even if the relative major tonic is the third chord in the relative minor, it’s still III (or bIII in certain methods of roman numeral analysis), not actually the I chord of anything unless you modulate to the relative major (in which case you are in major, not minor at that point). Therefore, naming the tonic of our minor scale “La” makes no sense to me, because La is the sixth scale degree of solfege, not the tonic, and the minor melody we are singing does not have a direct connection back to its relative major in that sense. This is why I prefer the Brightest to Darkest method, which goes with Do-based moveable do, and not the white keys method, which would go better with La-based (minor) moveable do. This is (so far) the primary musical sticking point I have with this book, otherwise I love it so far (being on the Solfa chapter now, there’s still plenty for me to read!). See here for a preliminary review of the book as I’ve read it through the first part.] [/endUpdate]

All of this also leads to our final concept for now:

Mode Signatures

One final thing to talk about here is the idea of mode signatures. The key signature is a familiar concept in tonal harmony music theory, the kind normally taught first in general music theory classes. Students are taught that if you see two sharps in the key signature, then you are likely dealing with either D major or B minor, and you can tell which normally by looking at the first note of the piece (Pro tip: the last note is actually a safer one to use as it's more likely to be the 1st scale degree than the first note, though either is probably going to work. If they are the same then it's almost a guarantee that's right).

In modal music that is aimed at people who are likely to not have had a full music theory course yet (educational music for high school orchestras or younger piano students, for example) they will often use a bit of a cheat. You will often see the key signature of the major or minor key with the same starting note depending on whether the piece is in a "major-ish" or "minor-ish" mode, then accidentals will correct to the real mode (A mixolydian is "major-ish" so they'd use A major (3 sharps) for the key signature and then cancel the G# with accidentals at every occurance to lower the 7th scale degree).

But you can also use "mode signatures" which are more common in music that is in a style that uses modes frequently and is not necessarily educational in nature. For example, Celtic fiddle music is modal, and non-educational tunebooks of fiddle tunes will often use mode signatures without comment. This is where we only include the sharps or flats that are actually used in the tune in the mode signature, so A mixolydian would show two sharps with no accidentals. This means that any given mode signature could be one of seven possible modes (for two sharps, D Ionian, E dorian, F# phrygian, etc) rather than two (D major or B minor), but in practice it's often not that bad. To go back to Celtic fiddle, in those styles, Ionian, Dorian and Mixolydian are the most common modes, with some Aeolian and very few of the other modes, so you only have 4 (or even 3) modes to consider, and from there you can use the last note of the tune trick to figure out which in most cases.

Mode signatures are useful because they declutter the music and make it easier to read. They also reflect the modal nature of the music more than key signatures with accidentals do. Once you are familiar with the style of music in question and know what to look for they can simplify your life rather than make it more complicated.

————————— Everything after this point is under construction starting May 27, 2024. Things may shift over time—————————

Examples of Real-World Usage

Here are some examples that demonstrate real-world usage of the modes. I’m going to expand this section over time until I’ve got examples for all the modes, but I’m going to start with a couple that are very common in one of my major types of music, Irish traditional music. In this genre, the most common modes are Ionian (Major), Mixolydian, Dorian, and sometimes Aeolian. If you see anything else, it’s probably a relatively recent tune. As more people have started exploring this music coming from other genres or other contexts, people have started writing tunes in other modes and scales. It was a favorite practice among the fiddle students at Berklee while I was there to write fiddle tunes for the various theory classes we had to take, so some of them got downright weird when we had theory concepts that haven’t historically been a part of traditional music of the Celtic diaspora, and people tried to find ways to write fiddle tunes using those techniques anyway.

But traditional tunes and songs make heavy use of the modes I listed above, so here are a couple of examples. I’m not going to show examples of Ionian right now, as that’s so common that it’s more or less the default (the main difference in my mind between Ionian and just plain old major is that Ionian should be diatonic. If you have chromatic harmony like secondary dominants, etc, then it’s major, not Ionian. But to my way of thinking, there is no real difference between tonal diatonic major and Ionian mode. See Modal Harmony below for more on that.

My personal favorite mode in Celtic music is Mixolydian, and many songs and slow airs feature that mode. One of the most well known ballads is called “Lagan Love”. Here’s a version from the Celtic Pop ensemble Celtic Thunder, from their album/show Storm:

I’m going to pull an instrumental slow air for Dorian mode. This is from The Chieftains album The Chieftains 7, and is a track called “No. 6 The Coombe”:

Aeolian mode is natural minor, and there is a difference of sorts between tonal minor harmony and aeolian mode / natural minor, which is that the 7th scale degree is a minor seventh above the tonic, which means the V chord is minor (and vii is actually bVII, and is major, not diminished). Again, see the next section on Modal Harmony. This phenomenon has led some people to argue that natural minor itself should be thought of as modal (Aeolian) and not tonal. In Celtic music, if you see “minor-ish” tunes or songs, they are much more likely to be Dorian, not Aeolian, but there are certainly some tunes that are actually Aeolian. One of them is a common Hornpipe, “The Rights of Man”:

Modal Harmony

See below for (a lot) more detail and nuance, but if you just want a quick and dirty guide to common chords in each of the church modes, here you go (capital = major triad, lower-case = minor triad, lower case with ° = diminished triad):

Ionian (basically diatonic major): I, ii, IV, V, (vi)
Dorian: i, bVII, v [minor] in Celtic fiddle; i, ii, IV in certain other styles
Phrygian: i, bII, vii
Lydian: I, II, vii
Mixolydian: I, bVII, v [minor]
Aeolian (natural minor): i, iv, bVI, [v minor]
Locrian: not used much, but i°, vii, maybe some others

This is a large topic, so I’ll try to cover the basics here but there are full books that cover modal harmony in much more detail. It also varies somewhat from one genre of music to the next. The version I’m going to cover here is based off of my experience in the worlds of Celtic fiddle music and to a lesser degree film music, and many of these concepts will apply to other genres as well, possibly with some modification. A good book I found specifically for Celtic music if you want to dive deeper is Celtic Backup for All Instrumentalists by Chris Smith, published by Mel Bay.

The most important consideration in the modern use of modal harmony is that we want to be sure we don’t get drawn into tonal (major and minor) harmony instead. Most people are so used to hearing music in major and minor keys that small hints of that can pull us out of the modal sound-world. To this end, we are frequently going to want to avoid root motion down a fifth. This applies to a V-I chord progression, but it also applies to any other motion down a fifth, particularly where the top chord (that might act as a V chord) is major.

Another component of keeping things sounding modal is that a lot of modal music is very drone-heavy, with the bass instruments frequently playing the modal “1” note to make sure that that note continues to sound like our home area (I’m going to call the “1” note a “tonic”, even though that might seem to refer to “tonal” harmony). You don’t have to drone in modal music, but it is a common sound in modal music. This is most obvious in some instruments used in these genres like various kinds of bagpipes, which have a drone built into the instrument (though it isn’t always droning on the tonic). You can also do it with any other instruments that are used in the style. It doesn’t have to be a sustained drone either, sometimes you can keep a groove going on the tonic, or even just frequently returning to the tonic.

This drone can also be used as a “pedal tone”, which means that as the chord changes above the drone, the drone continues to play the drone note without regard to whether it is a chord tone or a non-chord tone.

Another preliminary concept to discuss briefly is the fact that in many styles that feature modes, the music is primarily melodic and not harmonic. The melodies can imply chords without an instrument playing them, and in Celtic fiddle music, tunes are said to be “complete” in and of themselves without any harmony, or with only drones. In modern times, guitars have been brought into the music (particularly since the 1960s folk revival), and in some regions of Scotland cello and piano have been part of the music for centuries, but you can also play the tunes alone and they work just fine. This trait varies from region to region - in some fiddle styles double-stop “drones” are very common, especially when the fiddle was likely to be the only instrument in a given session.

Music in mountainous regions often works this way - until the past few decades it was very difficult to travel far in the mountains in most places, and fiddle music of the Southern appalachians in the US (for example) is much more drone intensive for that reason - forget about having a piano handy, guitar penetrated mostly in the 1930s and later, and having more than one or two musicians within easy range to have parties was a luxury (see Old-Time Fiddling Across America by David Reiner and Peter Anick published by Mel Bay for a lot more about this topic). Because of this, the music is very drone heavy on the fiddle and they make frequent use of “cross-tuning” to make the instrument more resonant and make drones easier to play (this is called scordatura in classical music - retuning the strings from standard tuning for special effect). Comparatively, in New England where pianos were common, the fiddle playing is more purely melodic (implying but not playing harmony) and the piano plays the harmony.

With some of those preliminaries out of the way, we’ll look at more specifics for modal harmony.

Modal harmony is functional just like classical tonal harmony. This means that there is a “1” note (the tonic) that is the focus of a given passage of music, and other notes and chords relate back to that note. We can assign numbers to the notes in the scale and roman numerals to the chords built on those notes just like we do in classical harmony. It’s the specific relationships that will change.

The convention I’m using here is a hybrid of one I learned at Berklee with classical harmony conventions. Upper case roman numerals refer to major chords, lower case refer to minor chords (and diminished chords which also have a ° next to the roman numeral, though as you’ll see we’re not normally going to use diminished chords in modal harmony). This is like classical analysis. The Berklee component is that I’m going to relate chords back to major harmony in one specific way - if the root of the chord is lowered compared to what it would be in major key harmony, I’ll label it with a “b” (flat sign) before the roman numeral. In classical music, the major chord on the seventh scale degree is labeled as VII in any key where that note is a whole step below 1 in the scale (natural minor or certain modes). I’m going to call that same chord bVII (“flat-seven major”) even in modes where it’s diatonic to the mode (and all chords will be diatonic to modes - we’re not normally going to use chromatic harmony in modal music, though check out the next section on Modal Interchange for more on that). This will also mostly apply to bVI and bIII more than other chords (bII in Phrygian mode and Locrian mode, though we’re getting a little ahead of ourselves here).

So the next major concept in modal harmony is to go back and look at the “Brightest to Darkest Modes” method that I outlined above. This is another area where this version of understanding modes really shines (in fact you pretty much have to use this method to make sense of modal harmony). Leaving aside Locrian for now, the other six modes either are major or natural minor, or are one note different from those. This “one note different” is going to be our magic note for modal harmony. In each mode, we are going to use the I or i chord, and then a major or minor chord that is made such by that one note that is different. Modal harmony of the sort I’m focusing on here is mostly triadic (as opposed to using seventh chords), and so every note in a scale can be the root, 3rd or 5th of a triad. Since one note is altered compared to major or (natural) minor, three chords will be altered relative to what they would be in major or natural minor. One chord will newly be major, one will newly be minor, and one will newly be diminished. We’re going to start by throwing out the diminished chord, and then our modal chords will mostly focus around I or i, and the major or minor altered chords. You can use other chords in a modal context, but the more you use other chords the more you risk coming out of the modal sound world, so if you are really trying to stay modal (and particularly if you are trying to stay in a specific mode - again, see modal interchange below), be careful how you use other chords. In particular, watch out for any chord progression that leads to root motion of a 5th between chords that are not V-I (it’s easier than you might think to wind up that way by accident). Also be careful of using V-I itself.

The one significant exception to this rule about avoiding root motion of a fifth is v-i or v-I (minor 5 to minor or major I). In tonal harmony we very specifically avoid using minor v, actually going out of our way to make it major V in minor key harmony. This is why I keep specifying natural minor in relation to modes. In classical tonal harmony we automatically raise the leading tone in minor harmony to make harmonic minor so the V chord is major (and vii is diminished), leading to the tonic-subdominant-dominant-tonic cycle found in classical common-practice functional harmony. This then results in an augmented second between scale degree 6 and 7, so to smooth that out they started raising scale degree 6 when it goes up to scale degree 7, making melodic minor. I’ve heard it said that if you see natural minor used, that’s actually modal and not tonal, using Aeolian mode rather than minor. For these reasons, minor v sounds modal and you can get away with that chord. This is found in particular in Mixolydian and Dorian modes as we’ll examine momentarily, and is actually a common chord in fiddle music as those are two of the more common modes in fiddle music.

Ionian Mode

This is effectively major, and to my way of thinking the main difference between modal ionian and tonal major harmony is that we stay diatonic in modal harmony and you can use chromatic chords (secondary dominants, etc) in major harmony. The main chords used are I, ii, IV, and V, but vi and iii are not uncommon (if you see vii° it’s more likely major, but really there isn’t much difference between diatonic major and Ionian mode, at least in the kinds of music I play). Note that here we are not that concerned about V-I, and Ionian mode mostly will sound like major.

Dorian Mode

Things will get a little more interesting here. This is the primary minor mode in Celtic fiddle music (if you hear a tune that sounds more or less like minor, it’s more likely to be Dorian than Aeolian if it makes use of note 6). Dorian mode is minor with a raised 6th note (moveable do solfege Le becomes La). This makes our ii chord minor rather than diminished, IV major rather than minor, and vi diminished rather than major. Throw out vi, so we get i, ii, and IV. In Celtic fiddle music in particular, we also throw in bVII and v [minor], and actually in most fiddle tunes I know the chords are likely to be i, bVII, and v rather than ii or IV (basically Mixolydian with a minor i). In most other contexts I hear dorian used in, particularly film music, vamping between i and IV is common. ii seems to be less common in Dorian mode.

Phrygian Mode

Not normally used in Celtic fiddle music, but common in other styles. I know many pieces that hint at Phrygian with a bII note somewhere, and of course in classical music bII is the Neapolitan chord, common in chromatic minor harmony. In a modal context, this one is common in middle eastern music (often modified further from the church mode Phrygian - see the section at the end of this guide for what I call “Spanish Phrygian”, also found in klezmer music among many other styles). The church mode Phrygian is a minor mode, natural minor with a lowered second degree (re becomes ra). This gives us bII (flat-two major) rather than ii, vii (seven minor) rather than major (or diminished in harmonic minor), and v°. Throw out the v° chord, and i, bII and vii are common phrygian chords. In Spanish Phrygian, I is major, with bII and vii.

Lydian Mode

The brightest of the modes, with an often magical or mystical feel. This one isn’t usually found in Celtic fiddle music, but can be used elsewhere. I associate it with Eastern European traditional music, and with film music in particular (though there it’s very clichéd). Major with a raised fourth degree (fa becomes fi), II is major and not minor, iv is diminished and not major, and vii is minor and not diminished. Therefore, I, II and vii are your standard modal chords. I sometimes hear V in there as well, but just be careful with that (and realize that “II - V - I” is just “V/V - V - I” - a very common tonal major progression). II - I is much more common, and much more Lydian sounding.

Mixolydian Mode

My personal favorite of the church modes - warm and dark. Very common in Celtic fiddle, along with Ionian and Dorian. Major with a lowered seventh scale degree (ti becomes te). This gives us bVII major instead of vii°, v minor instead of major, and iii° and not minor. Throw out iii°, and I, bVII, and v are the standard modal chords for mixolydian. IV can make its way in there too, but watch out: IV - bVII is root motion of a fifth! (This is not completely unusable but if you try that, you’ll need to go back to I immediately and make certain that I stays firmly established. IV - bVII - I might sound nice now and then, but if in doubt, avoid it. I would probably stay on I for at least twice as long as the others to help restore the sound).

Aeolian Mode

Natural minor. Sometimes found in Celtic fiddle - though look closely to see if it’s actually Dorian. The key note here is the lowered sixth scale degree (6 is le, not la - obviously not varied from natural minor, but relative to the other modes, and in particular from Dorian). i, iv, bVI are the common modal chords here, but v (minor) can also be used, as that is what distinguishes this mode from tonal minor (harmonic minor).

Locrian Mode

Now we come to the “odd one out” as I said above. Natural minor with a lowered second and fifth scale degree - the fifth is the new one relative to Phrygian mode (sol becomes se). On this one we can’t throw out the diminished chord because it’s 1! Used mostly when a very unsettled feeling is desired, it is not very common as a mode for a piece. Used more as a chord scale on diminished chords (so on the vii chord in diatonic harmony) in a jazz context. If you forgot this mode existed in terms of writing a piece, you would probably do fine, or maybe take that as a challenge to explore it and see what you can come up with!

So that’s a quick crash course in modal harmony using church modes. There is a wide world of modal music to explore, and it opens up all sorts of possibilities when used in other contexts. One of my students asked me why “all” music isn’t modal given the significantly greater options that you get from modes compared to “just” major and minor key harmony. You can do a lot with those modes too of course, especially once you explore chromatic harmony in a Harmony 2 class and beyond, and the reason might be simply historical and down to the “common practice” mindset of the period that we tend to study in music school (European classical music of the 1600s - 1800s and into the early 1900s). 20th century harmonic explorations have tended to get away from functional harmony, getting rid of the idea of a “1” note entirely. But modes have gained popularity at times in the last 100 years as people searched for other avenues to explore outside the European common practice world, and of course as demonstrated here they are still in wide use in many non-classical styles, and particularly traditional folk music in various cultures.

As we turn to our next topic, we’ll see another way to make use of modes that really blows the door wide open on the possibilities: modal interchange, or mode mixture (or modal borrowing - take your pick!)

Modal Interchange

Another major concept in modal harmony that’s worth exploring in some detail is “Modal Interchange”. I’ve also seen it called “Mode Mixture”, especially in classical tonal harmony sources, and at CSUN, I heard the term “Modal Borrowing”. We called it “Modal Interchange” at Berklee. The idea is straight-forward, but there are a lot of ways to execute on the idea, like a lot of things in music theory.

You can think of this as the “chromatic harmony” version of modal harmony. There are really two ways to approach this concept. At a fundamental level, the idea is that we can borrow notes (and chords) from one mode and use them in another, but you can either do this within one phrase, or between phrases or sections of a piece. In tonal harmony, we use modulation a lot, which is where the tonal center note changes over time (we start in C major, then modulate to G major, or to F major, or sometimes to Eb or Ab major (or to their relative minors), or really any key). We do this because a song gets boring if you don’t change it up over time, and one way to do that is to shift the tonal center. Modulation changes the tonal center, modal interchange changes the mode while keeping the tonal (modal) center the same. In classical music this usually involves flipping from the major to the parallel minor or vice versa (C major to C minor, or C minor to C major). But we can do this with any mode.

This is the way we do it between phrases or sections, and we’ll explore some examples below of that, but we can also do it within a phrase, and this can be either melodic or harmonic (or both). One common example of this is to use the bVI scale degree in a major (or major-ish) context - in C major, the sixth scale degree is A, but in C minor, the sixth scale degree is Ab, and in mode mixture, we can use an Ab in C major and call it bVI (“flat six”). At CSUN they emphasize moveable-Do solfege syllables instead of scale degree numbers, so the same change would take “La” (scale degree VI) and make it into “Le” (bVI). One of the most common examples of mode mixture harmony across genres is using the iv chord in major harmony (with I [major] as the tonic chord, and iv [minor] for that chord), or bVI (the chord) with a I chord (remember that upper case roman numerals are major, lower case are minor). bVI to bVII to I (major) is a common pop cadence in songs that use modal interchange or mode mixture.

You’ll find that this is more common borrowing minor (or minor-ish) chords with a major I chord than it is to do major (or major-ish) chords with a minor i chord. The most common classical mode mixture scenario in minor key harmony is the “Picardy 3rd” from Baroque period music, which is where a piece that has been minor suddenly ends with a major I chord (see below for an example - coming soon!).

Here are a couple of examples from the pop music world to start with (I’m still building this part out, so check back later for more!)

This first song I’ve chosen is Willie Nelson’s version of “September Song”, which is a great example of a song that uses a lot of minor key harmony with a major I chord, which gives this song an extremely wistful feel, appropriate for the lyrical content about the end period of a person’s life:

The other example I have right now is the song we used in my Harmony 4 class at Berklee to show this concept. This one sticks within a mode in each section, but changes between sections, flipping between Mixolydian and Dorian modes. This is “Norwegian Wood” by The Beatles:

Other Types of Modes

I discussed the modes based off of a major scale above, which are also often known as the “Church Modes”. You can take any scale as a starting point for developing modes though, and harmonic minor is a particularly interesting scale to play with in this regard, as it includes an augmented 2nd interval (3 half steps). In the case of harmonic minor itself, this augmented 2nd falls between the 6th and 7th scale degrees. It occurs because we raise the leading tone (the 7th scale degree) by a half-step in tonal minor harmony so that the V chord is major (or a dominant 7th), and the vii chord is diminished, just like in major key harmony. Here is a harmonic minor scale built on A:

But if we then take this scale as it is, and start doing the same process that we did with major, we can get a number of interesting scales to work with. The one I see the most often in the music I play is the fifth mode of harmonic minor, which has several names depending on who you talk to. The name I learned for it originally is “Spanish Phrygian”. This one starts on the fifth note of the normal harmonic minor scale, so it puts the augmented 2nd interval between the 2nd and 3rd scale degrees. Here it is, as the fifth mode of the A harmonic minor scale, so it will be based on E:

And now, if we transpose it so it starts on A:

Here’s another way to derive this scale, which will show why it’s called Spanish “Phrygian”. We will start by getting A Phrygian. Going back to the Brightest to Darkest method above, we know that Phrygian is a “minor-ish” mode, so we start with A Natural Minor:

Then we know to make Phrygian, we lower the 2nd scale degree by a half step, so B becomes Bb:

Now to make Spanish Phrygian, we take “normal” Phrygian and raise the 3rd scale degree by a half step, so C becomes C#:

Here is a famous classical piece that makes use of this mode, the “Aragonaise” from Georges Bizet’s opera Carmen (this is from the 1st suite for orchestra). The main theme starts in the Oboe after the introduction, and then it is played by other instruments. Here’s a video, and a snippet of the Oboe part showing the theme as it is originally stated (0:20 in the video, full score available here):

Capital-M Music

Music Theory Guides

How to Think About Modes

by Richard Bruner

Cheat Sheet Version (Click to Open)