Using V and v chord when melody alternates between harmonic and natural minor

Question

When using the harmonic (or melodic) minor scale for a melody, it is often combined with the natural minor, depending on whether the seventh is a leading tone going up to the tonic (in which case you'd use a raised seventh), or e.g. a melody going downward (in which case you'd use the natural seventh). This sounds very "normal", and a non-musician would hardly notice that you're mixing two different scales.

However, when writing a song with a melody that alternates between harmonic and natural minor, does this alternating between a raised and natural seventh extend to the choice of V or v chord? E.g. if the overall key is E minor, would you use both B and Bm chords depending on the local context? And would that local context be the melody, or the chord progression (i.e. would you use B when the next chord is C or another chord that contains the note E, and Bm in other situations)?

Answer 1

Melodic minor for up and natural for down simply is not how minor key music works. That is a short hand textbook rule.

...E minor, would you use both B and Bm chords depending on the local context?

Yes.

A lot depends on style. In classical music it really depends on whether the seventh degree is raised to act as a leading tone.

In the following lesson you can see how the raised ^7 moves to the tonic. But in bar 10 the ^7 is the lowered form, F natural. It is part of a descending line - not acting as a leading tone. Basically the raised form is used for cadential (tonic/dominant) harmony.

But that example has the ^7 degree in the bass. It doesn't quite address your question about cases when it is in the melody (treble part.)

The following is from a partimento lesson...

...where the lowered ^7 is in the melody and beat 4 of bar 1 is clearly the minor v.

The bass part is the actual content of the lesson and it opens like this...

...where the use of the raised ^7 - the G# in the bass - for the cadence is clear. At such cadence points we would definitely expect the major dominant V.

Both forms of the dominant are used in minor and the ^7 degree can be either lowered or raised in either a harmonic or melodic context and in either ascending or descending contexts. The difference depends mostly on whether the harmony is cadential, a dominant to tonic progression.

Answer 2

When you write a melody, you imply something about the harmony as well, and so you have some kind of a vague idea or gut instinct about chords, even if you can't or don't want to explicate any specific chords right away. You can do it either way. Think of chords first (for example by using voice-leading as a guideline for thinking up something) and place melody notes on strategic places in the harmony progression, fulfilling any other criteria like ups and downs, tension and release, rhythmic feel, expectation and surprise, etc. Or write melody notes straight away for example following the ups and downs and natural rhythm of lyrics, and then think of nice chords to support it while satisfying other "design criteria" like tension and release etc. Modern pop songs usually stick to colorless/tasteless/odorless minor or major pentatonic scales for melody, and backing chords live their own separate life.

In any case, if you want to do a Bm feel, you'll use a D note in the melody. Or if you use a D# note in the melody, you won't harmonize it with a Bm chord. Use both if you like.

Here's one in Em, with both Bm and B, chords first, placing melody notes on critical spots, with a rhythm. I guess it could go melody first as well, but if you write this melody without chords, you won't need a musical genius to come up with these chords.

Edit: I'll add my comment about the "going up" vs "going down" thing here. What happens with the melodic minor scale when going up is, it implies chords, namely secondary dominant - dominant - tonic. For example if the key has been established as Em, then even if played without accompaniment, the melody notes B - C# - D# - E feel like chords B - F#7 - B7 - Em. For some reason the melodic minor scale is often explained as some kind of natural phenomenon or semi-physical thing in itself that "just works" when going up, but IMO it's like a common short melodic phrase, with chords virtually embedded in it. It outlines a chord progression.

Why the melodic minor is not used all that often in descending melody phrases is that it requires a bit more imagination to feel a sensible harmony progression there. For example Em - B7 - F#7 - Em makes much less sense than Em - F#7 - B7 - Em. What comes to the harmonic minor scale's B - C - D# - E, it sounds like e.g. the chords Em - Am - B7 - Em. And descending E - D# - C - B works too: Em - B7 - Am - Em is easy to imagine there.

Answer 3

In lots of classical pieces the composer follows a not-so-obvious (to me) rule (it does make sense.) Ascending scale like use the raised forms of steps 7 and 8 and descending forms use the lower forms; at the same time, the minor v is used in non-cadential situations; the major V in cadential ones. Of course, the classical composers used the lower step 6 and raised step 7 commonly.

A couple of examples can be observed here. When a cycle of fifths (or fourths or circle depending on one's naming preference) is repeated, the v minor may be used in the first cycle and the V major at the end: i-iv-VII-III-VI-ii0-v-i-iv-VII-III-VI-ii0-V-i (or I). Similarly there are some renditions (can I say this for 1600s music?) of Greensleeves that go i-VII-i-v-III-VII-i-V-i.

About the only permutations that I have not seen (at least until the middle Nineteenth-Century) are the augmented chord on 3 and the use of a raised 6 as a neighbor tone to step 5.

What one sees (that may seem against the rules) are false relations between the raised 6 and 7 against the lowered versions in a bass vs melody.

Of course, the classical composers tended to think of the with the minor mode as a single object two mutable tones. They didn't separate the natural, harmonic, and melodic minors as objects in themselves; that's a more modern interpretation.