Are parent scales always major?

Question

As a classical musician, the notion of "parent scales" isn't something I encountered until I started visiting this website.

From context, I understand the concept just fine. But it seems that answers exclusively use major scales as the parent scale. Even an Internet search of "parent scale" results in several hits that specify "parent major scale."

Does this mean that parent scales are always major? Or are there perhaps different contexts used for the term "parent scale"? (Online usage of the term is...ambiguous at best.) I'm wondering if parent scales for diatonic modes are always major, but then parent scales for chords (or modes other than the diatonic church modes) are allowed to be something else.

Answer 1

It might depend on context and it might apply more to one instrument than another. So you could get a variety of answers. In short given a 12TET tuning and all the other caveats we have 7 diatonic modes, Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeloian, Locrian. Each being distinct in character each is contained in the Ionian or Major scale. So, playing in D Dorian puts you in the key of C major for example. And F Aeolian is in the key of Ab Major. In guitar blogs and online lessons we frequently talk about the parent major scale as a way of knowing where the key signature tonal centers are regardless of what position you are in on the neck. Why major and not parent Lydian? I have no answer to that except historical context. We have music written in Major and Minor keys, where the minor compositions would typically use melodic or harmonic minor. Indeed we can, and should, and do use the concept of a parent melidic minor scale when discussing the melodic minor modes used in Jazz. It is rare to talk about the parent Dorian but I think it makes sense. Take for example So What by Miles Davis. The tune is written in D Dorian, the Key of C. But no one refers to it as being in C. It is so strongly modal that saying it's in C (major) throws everything out of context. And I can tell you from playing it 1000s of times over the decades in my mind I default to "Parent Dorian Patterns" when moving through the change. I might be in the Major scale but I am hearing and feeling Dorian, otherwise it wouldn't come together quite right. I think that what we call Parent Scales depends on the application.

In the context described above I see the concept as picking a frame of reference for the ear and in my case (as a guitarist) the hand.

The fact that any mode in 12TET can be embedded in the Chromatic scale doesn't really make the Chromatic a parent in the above context. It is ambiguous in that there is no pattern, every note is a viable starting note and it always has a Chromatic character.

Answer 2

No, parent scales are not always major.

First, what is a parent scale, actually?

I think the usage of the term "parent (major) scale" is mainly due to how we have historically been taught the diatonic scales - I'd wager that most people start by learning the Ionian (major) scale first, next it's usually Aeolian (minor), then the rest.

To remember how to construct the rest of the diatonic scales (in 12TET), we learn that these are derived from a specific order of half-steps and their cyclic permutations; meaning that if we start from the major scale: [2, 2, 1, 2, 2, 2, 1], we can derive the dorian scale: [2, 1, 2, 2, 2, 1, 2] by moving the initial whole step to the end of the list. This commonly taught way of constructing/deriving the scales means that we usually have to think of a parent scale first, which is — out of habit-- commonly the major scale.

What's the alternative?

We can enumerate the 12TET notes from 0 to 11 and arrive at the definition of a pitch class set:

Here, the "initial" whole step that gets "rotated" around is highlighted in green, and the flattened/sharpened notes (from the perspective of the major scale) are given in bold.

According to the works of Forte and Rahn, we now examine these pitch class sets, and stipulate that one of them is the "prime form", while the others (the modes) can be derived purely by rotations. The prime (or "normal") form is chosen to be the one which is most compact, in this case the Locrian mode. In this context, therefore, we might call the Locrian mode the "parent scale" of the diatonic scales, which evidently is not a major scale. Note however, that due to the way we're taught, most musicians instinctively rather think of modes of the "major scale".

Further reading

Here, I'd strongly suggest to check out Ian Ring's great website, which lists all 2^11=2048 scales with a lot of analysis and clickable midi examples. Most importantly, he found that by representing a scale in binary form major scale: 101010110101 (picture this as if each note on a 12-tone keyboard being on or off, reading from right-to-left!) we can directly derive a decimal representation major scale: 101010110101 == 2741 and if we do this for all the modes, we can find the "most compact set" is the one with the lowest decimal number (the locrian scale).

So what does this tell me about any non-major parent scales?

Using Ian's scale finder, it's extremely easy to find the modes of any scale; take for example the Ultralocrian scale with its modes: Locrian Natural 6, Major Augmented, Lydian Diminished, Phrygian Dominant, Aeolian Harmonic, Harmonic minor scale, all of which are clearly not the major (i.e. Ionian) scale.

Answer 3

The answer would be no. I would like to offer a particular example of parent scale, namely the melodic minor scale. The reason why I think it's specially relevant to this discussion is because its modes are a very important part of what's called chord-scale theory, which is of interest to jazz students, etc. In the context of C-S, these modes are a natural way to complement those of the major scale, as the two parent scales (major and melodic minor) share some characteristics of harmonic and melodic interest. So, in a similar way to when you think of dorian (2nd mode of major) as related to the "m7" chord, you think of altered (7th mode of melodic minor) as related to the "7alt" family of chords (that's a "7" chord with its 5th and 9th raised or lowered).

Answer 4

I have only seen "parent" scale and chords in relation to the jazz "chord scale system." My impression is the standard major and minor scales presented in textbooks (major, natural minor, harmonic minor, and melodic minor ascending) are the common "parent scales." Sometimes the term "parent" is used, sometimes "nth mode of a scale" is the wording used. Either way the concept is the same. Probably no one will use natural minor as a parent scale, because it's just a mode of the major scale.

Some minor mode examples are the altered scale which is the seventh mode of the parent melodic minor scale, or the Lydian dominant scale which is the fourth mode of the parent melodic minor scale. Harmonic minor can be a parent, like the Freygish scale is the fifth mode of harmonic minor. Charts abound on the internet of the all modes of the parent harmonic and melodic minor scales.

While I read "parent scale" a lot, I've not seen a common term like "derived scale" or "synthetic scale" for all the "scales" you get from a parent.

Some scales derived from parents are culturally significant, like the Freygish scale. Others like the super Locrian double flat seventh are not.

The parent scale idea seems to cause a lot of confusion about mode, key, and key signature. Also, I've never seen any of these sources make a distinction between a mere collection of tones - like the modes of harmonic minor - and the modes of real musical cultures - like the modes of Jewish music. The same goes for the modes of major versus the Medieval modes. The former suggests you can substitute any number of (sort of) similar scales over certain chord types, the later are cultural expressions and tonalities for entire compositions.

Regardless of my misgivings, this stuff is all over the internet.

Answer 5

In western music, I would think that the Chromatic scale might be considered the Parent Scale, although when we discuss chord formula and modes, we usually are discussing The Major Scale, but I think that has to do with narrowing the focus of the discussion in order to understand a particular topic more clearly. Perhaps the Chromatic Scale could be referred to as the GrandParent scale. I've only studied music theory on my own, but I've been doing it pretty regularly for a few years now and it seems clear to me that the usage of the word parent is mainly descriptive of the place of origin for whatever concept, idea, scale, mode, etc. mostly intended to help us understand structure.