Harmonic and melodic minor chord function

Question

If the natural minor and major chord functions are :

Tonic Function: I, i, and vi - The home chord sounds at rest. It usually provides the beginning and ending for most progressions. Sometimes the submediant (vi) can be used as a substitution for tonic at the end of a phrase. Such a substitution is called a deceptive cadence, as it usually comes as a "surprise."

Mediant Function: iii, vi, bIll, bVI, and bVII - Mediant chords have a weak and not entirely determinate pull, but don't sound resolved. They usually provide a link between chords of stronger character (Le. tonic, subdominant, and dominant chords).

Subdominant Function: IV, ii, iv, and ii^o - These have a relaxed pull towards tonic that sounds as if it "falls" back into the tonic chord, or move to the tonic by means of another chord, namely the dominant.

Dominant Function: V, vii^o, and v - They have a stronger pull to tonic and sound as if they're "leaning" into it. Moving to any other chord besides tonic comes as a bit of a surprise, though popular music has tamed the V7 - IV progression so that it is fairly typical.

; then what are the harmonic minor and melodic minor chord functions?

Answer 1

The raised leading note, compared with that in the natural minor, makes the V-I even more convincing. A semitone move is usually better for resolution than a tone.This was the reason that the harmonic and melodic both had a raised leading note.With the melodic, coming down was fine, it followed the natural minor's notes. Going up, though, the gap between notes 6 and 7 was deemed too large, so the 6th was also raised, making the last part of the melodic scale the same as the parallel major.

Some of the functions described are subjective, and also depend on the previous couple of chords as well. The IV (with now maj 3) might well act as V/V to reach the relative tonic, maybe more pointed than going v/V. viio also acts as a dominant. Most of the feel, therefore the function, can be perceived by listening to the triads, and playing appropriate chords after them.

Answer 2

Strictly speaking, the functional harmony labels are: tonic, pre-dominant, and dominant.

Tonic Function: ...and vi

Tonic function should really be reserved to I or i. The whole point of the deceptive cadence is a move from a dominant to a non-tonic chord. For the deceptive cadence definition to make any sense vi cannot be considered a tonic chord.

Mediant Function: iii, vi, bIll, bVI, and bVII

bVII should not be included here. It is not built upon, nor contains, either the mediant or submediant degrees. It's the sub-tonic chord. Being neither tonic nor dominant, it should go into the pre-dominant function category.

I understand that you mean 'mediant function' to include mediant, submediant, and the various chord qualities between major and minor. Of course they are all mediant in the sense that the various roots are a third away from the tonic, but I would caution against equating that to mean same function.

The sub-mediants function mostly the same regardless of mode, but iii and bIII tend to function differently. iii is a fairly un-common chord. When it is used it is likely to be part of a sequential progression like I IV, viio iii, vi ii... or I V6, ii V6/ii, iii V6/iii.... By comparison, bIII in minor, might be part of a tonicization or modulation to the mediant.

what are the harmonic minor and melodic minor chord functions?

"Harmonic minor' and 'melodic minor' are names of scales. I'm sure you know that, but in terms of harmony and generating chords those scales should be understood as variations of the natural minor, the diatonic set of tones.

The system should be thought of as 'minor key functions' with scale degrees ^6 and ^7 being raised or lowered traditionally depending on the movement of the bass which generates the harmony. There is also the idea than a raised ^6 is used when the ^7 is raised to avoid an augmented second. (That would be a purely melodic treatment of the tones.) The point is such treatments are local and happen at the moments when either a dominant chord is desired (or necessary for a cadence) or a melodic segment is avoiding and augmented second.

Those momentary, localized treatments of ^6 and ^7 aren't the traditional basis for defining the set of diatonic minor chords.

The diatonic chord set is:

i    iio  III  iv   v    VI   VII  i

The chords to add to that diatonic set are generated by the harmonic treatment of ^6 and ^7 and are IV V viio...

i    iio  III  iv   v    VI   VII  i
               IV   V         viio

Finally, placed into functional categories...

TONIC: i

PRE-DOMINANT: iio, III, iv, IV, v*, VI, VII

DOMINANT: V, viio

(*) I'm using the definition of a functional dominant as a major chord built on the ^5 scale degree, or the diminished chord built on the leading tone.

Answer 3

then what are the harmonic minor and melodic minor chord functions?

The harmonic and melodic minor chords of the V are both the same:

e.g. a-minor:

in opposite of the natural mode where the triad of the V is E G B (with the minor 3rd) in harmonic and melodic a-minor the triad of the dominant E contains a major 3rd: E G# B or when it is V7: E G# B D

The harmonic and melodic minor triad of the V have the same function as the V of the major parallel, that is a function the dominant which confirms the tonic

The leading tone G# has a stronger tension to the tonic A (root) than the natural 7th tone G. The sharpening of the 7th of the scale is derived from the E major scale which is the scale from the fifth tone in A major and the triad of E is the E major chord ( E G# B is the dominant = V of A-minor) is identical with the dominant of A major)

the function of the #7 is confirming the tonic.

this is influencing also the VII that becomes the function of a dim7

the III (C E G#) is contains an augmented 5th leading to C F A

all others triads are identical with natural minor, if not the 6th is altered then the IV is identical with the the major sub-dominant (do you say predominant?) and the VI° is another dim7

(just for helping beginners - who will read one day your question - to understand what function in music is meaning:

http://openmusictheory.com/harmonicFunctions.html

Answer 4

The harmonic and melodic minors have more of a melodic function, and the chords are adjusted to incorporate the changes in melody. They are basically chords that are borrowed from the parallel major key and do not change the chord progression much at all.