Non Diatonic Harmonization?

Question

First of all, I'm a self taught musician. I have a basic understanding of music, and I can play piano too. I understand the theory behind diatonic scales and how the harmony works. I have learned the major, minor, diminished, and augmented chords, and inversions too, as well as the basic 7th and 9th chords.

Now I want to compose music for a short film. I have already planned to get what plugins I needed for my DAW, and I have even come up with some tunes which I'm really happy with.
But because I'm composing for a film in the thriller genre (sort of), some of the tunes don't fit in the normal major/minor scales. I understand that's how film music works sometimes, but I'm still scratching my head (maybe because of my OCD lol).

For example:

• the melody notes (C, E, D#, C#),
• with the chords (C minor, D# Major, C# minor)

A second example:

• the melody notes (G, F#, D#, D),
• with the chords (G minor, C minor)

These are just some simple examples to clarify.

When I play all that, for me it sounds good and flows well with the scene, but my mind really overthinks about it: "What scale is this even?". The melody notes are relatable to the chords at least, and most of it and sounds good too — nothing felt off or unrelated.

So I'm really worried, am I doing something wrong? or is there no rules as long it sounds good together?

Answer 1

Put very simply, the 'rules' have developed from what sounds good, not vice versa!

Those 'rules' have been manufactured by musicians over many centuries to guide other musos and make their composing easier. But, making 'rules' for every situation or genre would be virtually impossible, and they would (and do) get broken every day.

Your ears are far better judges than following any 'rules' - some of which your ears will actually agree with, a lot they'll disagree with though.

Use those 'rules' as a datum point for what you're doing, and if you're happy with the end result, so be it.

Answer 2

or there is no rules as long it sounds good together...

This is essentially true, there are no rules. But there are tools!

I can make several suggestions:

1. Secondary dominants. E.g. in the key of C major one could harmonize C and E notes with C chord, and then D# with B7 chord, which would be a secondary dominant for E chord, but resolving deceptively to C#- instead (edit: after playing this example I realized D# in B7 is a leading tone that is expected to resolve upwards, to E, so that's not really a textbook example. Perhaps this is what earned me a downvote?)

2. Other scales than the most common major and minor scales. E.g. you could base the motif C E D# Db on C altered scale, or C half-whole scale, and use a chord or chords using appropriate extension. E.g. the whole motif could be harmonized with Calt chord.

3. Modal substitution. In the key of C there is no D# (or Eb) note. But there is Eb note in C minor. You could harmonize that note with some chord from C-minor, e.g. using Ab chord. Similarly C# (or rather Db) is present in C phrygian and C locrian modes.

4. Chromatic scale. You can simply treat the notes as intentionally dissonant and not belonging to the scale, and not suggesting any underlying harmony.

5. Modulation. At some point your composition may simply move to another key entirely. You may then come back to the original key – or not.

It's a good idea to experiment by your own, and in the end you always need to follow your ears, but there is also plenty of theory that can help you with the process. Definitely you don't have to limit yourself to chords using diatonic notes.

Answer 3

"What scale is this even?"

The first example could be a segment of a diminished scale. There is a lot of ambiguity in diminished scales, because you can select various scale steps to create minor, major, and diminished chords.

The second example is a harmonic tetrachord and could be the top tetrachord of a G harmonic minor scale. Both chords Cm and Gm fit very comfortably in that scale.

Both tone collections offer lots of possibilities for eerie or dramatic music.

In film scores a lot has to do with orchestration. Tempo/dynamics/rhythm will have a huge impact too.

If the film were a musical (like The Sound of Music) or required a traditional instrumental theme (like Star Wars), then you would need a solid understanding of the theory behind melody, harmonizing a tune, form, etc. The kind of stuff you would get from a college music theory textbook. You would need to know how to write things like 32 bar songs and symphonic type themes.

If the film doesn't require that kind of traditional music, a lot of expression can come from just orchestration. Unless that orchestration were purely percussive, you will obviously need some kind of pitch material, but you don't necessarily need full songs and themes. Your two example pitch collections would seem to be enough. Tempo/dynamics/rhythm would become critically important in the absence of traditional melody and harmony.

You mentioned thriller genre. That makes me think the Mission Impossible theme. I think it's a good example of the non-traditional approach. Rhythm is really important and the the 5/4 time signature is iconic. Listen to the orchestration. In terms of traditional melody and harmony it's very basic: minor pentatonic in bass with a chromatic descent in the top line, chord wise it essentially elaborates only an A minor chord the whole time except for a short diversion transposing to Dm. This isn't song writing, it's groove and riff with dazzling orchestration.

Compare that with song based in a similar film genre, something like the song Goldfinger.

Non Diatonic Harmonization?...So I'm really worried, am I doing something wrong? or is there no rules as long it sounds good together?

You're the composer, so you need to know what your working toward. It doesn't need to be traditional song or symphonic writing. If you're aiming for a theme like Goldfinger your harmonic material is probably lacking. But if your trying to just set a mood/emotion, the harmonic material seems like enough and harmonization, in the sense of a song like Goldfinger, is not really a concern.

Answer 4

So I'm really worried, am I doing something wrong? or is there no rules as long it sounds good together?

If it sounds good to you, then you applied some "rules" i.e. internal logic. Every style has its own set of rules, rules are style-specific. But you can make music in a style without being able to explicate the rules, just like you can speak a language without having studied the syntax or grammar of that language. You know the rules even if you don't know them. Music is a language, and languages are best learned through examples and repetition, not through abstract theory.

If your music doesn't follow the rules of some particular style, it doesn't mean that there are no rules in your music. It can help you work with your music if you can explicate a clear set of rules for it, but it's not a requirement. You can make music by ear. If you keep making music, you may gradually identify some rules like "with this melody note I always use this chord before this", and that will be your own theory and your own rules.