Different scales for chords and melody

Question

I haven't had any real education in MT so I might ask the wrong questions or my confusion might be based on lack of fundaments so please bare with me and I will try to explain.

Starting to learn MT and harmony I've been only familiar with music that is based on one scale from where most of the chords are taken from and the same scale is also used for the melody and sólo. Of course I understand that non diatonic chords and notes can sound great at the right moment.

But then I seem to encounter exceptions to this that sounds amazing. But I'd like some explanation on how this works. These are some of the things I've encountered if I've understood them correctly.

In jazz improvisation it seems that each chord can be understood as a whole scale and the improvisation solo will change scale for each chord. So the i guess that song is not said to be played in a certain one scale?

I realised blues can be played with a scale more like the minor for the solo but the chords accompaniment being in the mayor scale? Is this correct?

Same seems to go for klesmer music using the freygish scale for playing solo but often when I see instructions for a backing track the chord seem to be from a normal minor scale?

Answer 1

It would help if you have an example of a song. Otherwise you will get some vague abstract answers. Like the one I'm about to write.

First of all songs are often played on one scale. Just because you learned that some other scale matches this or that chord does not mean that the simple Major scale will not work.

There are several items at play here.

1. Often music changes key. One of the most common cord changes in Western classical music is I --> IV and I--> V, and reversed, IV-->I and V-->I, and any combination of movements within the set {I, IV, V}. These are major chords on the root, 4th and 5th degree of the Major scale. One can play the IV or V chord without changing key, but it sound very cool if you do change key. To that end when classical (and jazz) pieces move from the I chord to the IV chord they will often add an accidental in the original key, i.e. a flat 7th. As an example, a song in the key of C maj modulates to F maj by making B flat in the C major scale. The reason I point this out is that if you think of the song as being in C then you have "out of tune notes that work". But if you think of the song as modulating then all you did was play the melody in a new major scale. The scales that start on the 1, 4, and 5 of any key share 6 out of 7 notes and are called compatible keys in Western music.

2. Along the lines of the above sometimes a composer or arranger will add many chords in the circle of 5ths or the circle progression to prepare the ear for the key change. In Jazz this is most common and one sees an abundance of ii-->V-->I progressions where the I could be any chord in the original key, major or minor. This always sound good because if focuses the ear to hearing resolutions to each chord in the original song. To better understand this you need to learn about the perfect authentic and plagal cadences in Western music. Suffice to say the inclusion of these extra chords has "meaning" in a classical sense because they are leading somewhere, yet they may all be outside the original key of the song.

3. Another trick in play involves chord substitutions, specifically the tritone or flat 5 substitution. This type of substitution creates a chromatic chord progression that works but is "out of key" relative to the original chord. This idea works because the two chords share enough common tones that have the correct movement that one hears good harmony.

4. Keep in mind that a single chord can belong to more than one key and more than one scale. Some very exotic that don't even exist in classical western music. A Jazz standard might be written on the Major scale but once a player begins soloing they might want to walk away from that template to create really exotic ethnic sounds. This does not mean that the original song was somehow NOT in the major scale. We take liberties to create more ideas than traditional theory would support.

5. One of the key ideas that is expression in some of the above items on the list is leading tones. When we alter chords or add out of tune notes they aren't random. They are usually inserted to strengthen resolutions, and these have semitones like 7-->8, 4--3. In the case of the b5 sub you also have b2-->1.

The idea that chords have corresponding scales is somewhat artificial. It has value and is a valuable way to connect melody lines to chords but it's not a foolproof algorithm to understanding improv or chord-melody relationships. Sometimes things just work because they sound good. Western music theory describes a small subset of things that sound good but is not necessarily the standard against which all other things should be compared. Rather than asking "why does the blues work when there are notes that don't match the chord" one could ask "how is it than classical music sound good when they never use blue notes".

Answer 2

Whether a piece has chords (and associated scales) that all fit one pitch set, or whether each chord takes us into a quite different territory, there's one point that I think might have escaped you.

The notes of the chord or the 'scale of the chord' are a framework, not a restriction. Other notes may be (and frequently are) played. A simple example is a 'blue' minor 3rd played along with a major triad. Sometimes these out-of-scale notes (I won't say 'wrong' notes) are just decoration. Sometimes they are used systematically to give a new flavour to the basic harmony.

Sometimes it's useful to think of the 'scale of the chord' as having different notes in the second octave to the first.

It's also useful to remember that while jazz is great, most music is not improvised over a chord sequence. It's very specifically composed and orchestrated. For some really wild stuff, look at how great composers from Bach to John Williams (to pick just two) constructed their music.

Answer 3

It's like just about everything we learn from scratch. In maths, we learn early on that we can't take 5 from 3. At that point, it's all we need to know. Negative numbers don't need to exist till later!

Music theory starts with diatonics, and the more simple songs that use them. Harmony based on that is a very good start point. If we didn't follow on with more maths studies, we might well not consider negative numbers!

Imagine being told in early music theory that any note can and will fit with any harmony (as it can and does). Not sure where that would leave us, except trying blindly (deafly?) to sort out music with no boundaries. So, we start with the more simplistic, easier to comprehend, 'facts'. And it would seem, from reading so many questions on this site, that that's about as far as it went. 'I learned about that, so it should apply to just about everything.'

That certainly was not a rant - just an observation.

Now - watching a film in monochrome (b&w) that suddenly changes to colour is a lovely experience. Analogy to that - a diatonic piece changing with some chromaticism. Literally as well as physically. And that's where your second paragraph comes from. Using notes/harmonies other than the diatonic ones make a piece more interesting. Those seven notes work well together, but suddenly there's something we maybe weren't expecting thrown into the mix. And why not? Certainly not 'cos theory says not!

On the jazz theory: some say each chord can begat its own scale, or set of notes. It's how a lot of us think, on occasions. It's a formula that's been proved to work, so why not?

On Blues: true, there are 'special scales' that are used in Blues - major and minor Blues scales - better players will not just stick to minor , over the commonly found major (or 7th) chords. Counting up the available notes, then, I think there are only two that won't be included. And I know at least when I play Blues, those two also come out to play!

So, to sum up, as I say to students (eventually!) 'any note, anywhere, in any key, can and will fit - if you know what you're doing'. Continue with your journey through music theory, and it will become more apparent, the more you delve!

Answer 4

In jazz improvisation it seems that each chord can be understood as a whole scale and the improvisation solo will change scale for each chord. So the i guess that song is not said to be played in a certain one scale?

Yes, you can improvise with the tones of the scale of the any chord of the lead sheet.

I realised blues can be played with a scale more like the minor for the solo but the chords accompaniment being in the mayor scale? Is this correct?

This is correct: you can use the notes of the parallel key (e.g. A => a-minor) and get a bluesy sound.

Same seems to go for klesmer music using the freygish scale for playing solo but often when I see instructions for a backing track the chord seem to be from a normal minor scale?

Do you mean Phrygian?

All the modes contain the same tone reservoir of la ti do re mi fa so but they just start with another root tone. Aeolian = la, Dorian = Re, Phrygian = Mi etc. That's why you all tones will fit for the improvisation, but you must be aware what tone is the root tone, because this will have an influence on the improvisation motifs.

Answer 5

I've been only familiar with music that is based on one scale

Aside from folk and nursery tunes most music doesn't work that way. Two technical terms to learn are modulation and tonicization. Both are about temporary key changes, but modulations are relatively long, like a whole phrase or section, tonicizations can be as brief as two chords. Terminology aside even very short pieces usually have some kind of move to a new key/tonal center.

In jazz improvisation it seems that each chord can be understood as a whole scale...song is not said to be played in a certain one scale?

That is the "chord scale system." It's a teaching method. Historically jazz musicians didn't not use that. It was a teach method developed in the 1970's. The fact that many songs are not confined to a single scale is not a result of the chord scale system. That system provides no real insight to understanding tonality. Songs are not confined to one scale, because it is normal for songs to move in and out of different keys/tonal centers.

I realised blues can be played with a scale more like the minor for the solo but the chords accompaniment being in the mayor scale? Is this correct? Same seems to go for klesmer music using the freygish scale for playing solo but often when I see instructions for a backing track the chord seem to be from a normal minor scale?

Yes. The theoretical explanation is the basic tonal structure comes from the chord roots and the primary degrees of the tonic, subdominant and dominant, while the tonal or modal "color" comes from other harmonic tones, the thirds and sevenths of chords or the modal scale degrees. That's a lot of technical jargon. It's easier to simply describe the practice. For example, a basic blues sound is accompaniment with all dominant seventh chords on I IV V with melody based on minor pentatonic/minor blues scale.

The main thing to say is music which deviates from purely diatonic is not unusual. Chromatic chords, clashing tones like in the blues, etc. Those things are normal within various harmonic styles.