All about 6ths

Ok folks, after analyzing my so-called progression, I realized that I don't really know the proper terminolgy for the 6th note of a diatonic scale.

The 6th changes depending on whether you're playing a major or a minor scale, so is it called a major 6th and a minor 6th accordingly? Refresh my memory.

The 6th is tricky usually it remains the same because it is surrounded by the #5 and b7. In harmonic minor you do have the b6th scale degree, but in only extreme cases is it used as a chord tone. Like I was discussing w/NTM in a previous post, when the b6 is added to the chord it becomes a inverted major7th chord.

I must be missing something . . . doesn't the note change for major and minor?

For example, in A minor, the 6th is F. In A major it's F#. So would A to F be called a minor 6th, and A to F# a major 6th?

no the note doesn't change for maj or min...w/a root of A the 6th added to the chord would always be F#, unless notated w/ a b6 (F)

Ok, so in a minor scale the interval is called a flat 6th. And in a major scale it's just called a 6th. The 3rd chord in my infamous progression would still be an Am6, right? Because you're just adding an F, the 6th scale tone.

What about diminished 7ths? I remember you tried to explain diminished chords to me a long time ago. A diminished 7th interval is the same as a 6th, right?

Not Quite.
All intervals are major and minor, except for 4th's and 5th's, which are perfect, diminished, or augmented. So yes, there is a major and minor interval of a sixth, the only problem is that the minor 6th is enharmonic to the augmented 5th. So, when documenting a sixth chord only the major 6th is used. If you wanted to label a chord tone as a minor 6th you would have to say b6. But like I said, adding the minor 6th interval into the minor chord creates a inverted major 7th chord. Ex:

Amaj.6 (A, C#, E, F#)
A minor6 (A, C, E, F#)
A minor b6 (A, C, E, F)

Fmaj7 in 1st inversion (A,C, E, F)

So yes, maj and min 6ths are talked about within intervals and melodies, but only maj 6ths are recognized within chords. Such is also true with the intervals of 9ths, 11ths, and 13ths.

[Edited by chris mood on 10-28-2003 at 11:40 PM]

Originally posted by Christoph

What about diminished 7ths? I remember you tried to explain diminished chords to me a long time ago. A diminished 7th interval is the same as a 6th, right?

Yes. Technically there is no such thing as a diminished 7th interval, 7th intervals are only major and minor. So diatonically the diminished 7th chord is composed of the root, minor 3rd, diminished 5th, and 6th scale degrees. The tertian method of labeling chords though notates the 6th scale degree as a double flatted 7th.

Dim7 -

Yeah, it just makes more sense to me to think of it as a diminished 7. The chord is called a dim7 after all.

Originally posted by chris mood

Amaj.6 (A, C#, E, F#)
A minor6 (A, C, E, F#)
A minor b6 (A, C, E, F)

Ok, but I thought chords were always named according to the scale in which they belong. Like Am6 . . . the 6th tone of the A minor scale is F, so it's implied that it's a flat 6th. You don't have to write the flat. For Amaj6, the 6th tone in A major is F#, so it's an A6.

According to that logic, the A minor6 that you wrote (A, C, E, F#) would be an Am-maj6. That makes a lot more sense, because you only specify the notes that are out of the corresponding scale. The F# is not in A minor, so you have to specifically call it a maj6.

The diminished 7th in diminished 7th chords is a 6th, but it helps knowing it's a 7th and spelling it as such when you need to use this chord. They are a tool for modulation, because each note in the diminished 7th chord can be a diminished chord and be used to go to any key where that tone is a diminished chord in a scale.

Take a B diminished 7th, B, D, F, Ab. I would have been in the key of C major. My options of the next key I can go to are Eb major, using D - F - Ab. Or F# major, using F - Ab - B. Or A major, using Ab (enharmonic G#) G# - B - D. Makes those far away modulations easy. C major to F# major is pretty far away.

As for the minor 6th chords, they are a mess. I agree and thought the same thing when I first heard of them. In the the spelling the "minor or major" refers to as the triad, not the interval from root to sixth. However some people write them is different, I've seen Am6 for A, C, E, F. Then seen Am#6 for A, C, E, F#. That makes more sense to me, but then again everybody does it different. Chris is right though, when you see a Am6 it usually means A, E, C, F#. Because A, E, C, and F is really an inverted an Fmaj7 chord. F, A, C, E but with A in the bass.

Originally posted by noticingthemistake

In the the spelling the "minor or major" refers to as the triad, not the interval from root to sixth.

Very well said.


Think of 9th chords, whether you play a maj. or min. 9th the 9th is always the same. Same w/11ths and 13ths.

The minor 6th chord as a i chord would appear diatonic in Melodic minor.

Here's the one I have a real big problem with;
Caug7th or C+7
People always play this one wrong. Caug7 is technically C7#5. Like NTM said, the chord quality is based off the triad (CEG#), the 7th is dominant (Bb). The notes (CEG#B) is Cmaj7#5 and is always documented as such. And for those of you who try to figure out what the interval of a augmented 7th is and add it into the chord, well there's no such thing, an aug.7 interval would just be a repitition of the root.

ahhhhhhhhhh, I've been metamorphed into a grizzled veteran.
Grizzled Veteran / translation :"Get A Life!":( -LOL-

Am6

Ok, I don't think you heard what I said. I know the 'm' refers to the triad, otherwise by just looking at that you wouldn't know to play C instead of C#. I was saying that because the minor 6th inteval is in the key of A minor by default you don't have to specify that it's a flat6.


C+7

x
5
3
6
3

Is that right?

Oh, and congrats on the Grizzled Veteran thing. I don't get such honors as a mod.

Originally posted by Christoph

Am6

Ok, I don't think you heard what I said. I know the 'm' refers to the triad, otherwise by just looking at that you wouldn't know to play C instead of C#. I was saying that because the minor 6th inteval is in the key of A minor by default you don't have to specify that it's a flat6.

*Your assuming the minor 6 chord is going to be a i in minor. What if your in the key of Gmaj and you are using the min6 as a ii chord? Then F is no longer the diatonic note, F# is.

C+7

x
5
3
6
3

Is that right?

Yeah, this voicing works nice to: C7#5 (8x899x)

Originally posted by chris mood

*Your assuming the minor 6 chord is going to be a i in minor. What if your in the key of Gmaj and you are using the min6 as a ii chord? Then F is no longer the diatonic note, F# is.

Arghhhhh!....I never thought of it that way before. As usual, you've opened up my eyes.

Originally posted by Christoph

Am6

Ok, I don't think you heard what I said. I know the 'm' refers to the triad, otherwise by just looking at that you wouldn't know to play C instead of C#. I was saying that because the minor 6th inteval is in the key of A minor by default you don't have to specify that it's a flat6.

The tonic chord in a minor key is rarely played as a 6th chord. Either way, b6 or n6. I think the reason is they don't sound as they the have hit "home" or resolved, being too tense. Except the thread where I was discussing that with chris, but that's because I wanted that tension in there as I explained.

Minor 6th chords usually occurs within the moving part of a chord progression. Like Chris said with the ii chord in a major sequence, but don't forget the iii chord either. Try even playing the ii chord as a m6/9 chord, especially if you want to instensify the 6th harmony. I kind of like the use of 6th chords on the iv chord in either major or minor. Try going from Fm6 to Cm(7), or Fm6 to Cmaj for a romantic sort of sound.

Congrats on the being grizzled chris. Bad thing is though is I've been here a year less than you and I've almost caught up to you. 'LOL'

iii chords are touchy as 6th chords, becuase the 6th within them is a # root, sounds more like a modulation, same w/iii chords being minor 9ths, rarely seen. The i6 is actually quite common, especially in jazz.

I always tought it would make more sense to refer to these chords as diminished 6th chords. The double flat 7th makes for some strange enharmonic modulations. Ex;
Cdim7 (C Eb Gb Bbb) technically the Bbb would resolve to Cbb.

Haha. Oops, I don't know why I said iii could be a minor 6 chord. That creeped in there for some reason. No you won't see a iii minor 9th chord often, you may see it in a melody over a iii minor chord. About a tonic chord being minor 6th chord, I not sure about that. Your a jazz musician so you probably know more, but I would think it would be a minor 13th chord before a minor 6th.

As for the diminished seventh, I can see why you see it that way. Good point, and I also know alot of musicians especially in jazz will use a diminished seventh chord as a sub for a dominant or secondary dominant. Especially since the first inversion of a V7(b9) chord and the root of a VIIo7 can act as a leading tone to the tonic chord.

Since each note in a diminished seven chord can be considered it's root, you can take that a step farther by saying an inversion of that dim7 chord can be considered the leading tone to a new key's tonic. I use the later more since I don't play much jazz, but it is a nice variation to play with the listeners mind. I like to do that every once in a while. :D

[Edited by noticingthemistake on 10-29-2003 at 03:18 PM]

Originally posted by noticingthemistake

Since each note in a diminished seven chord can be considered it's root, you can take that a step farther by saying an inversion of that dim7 chord can be considered the leading tone to a new key's tonic.
[Edited by noticingthemistake on 10-29-2003 at 03:18 PM]

That's what I was talking about, Bbb resolving to Cbb is quite wacked. By referring to dim7 chords as dim 6th chord all of the enharmonic wacky spellings would disappear.

6th chords
The minor 6th is used a lot within a jazz context when a song modulates from Major to relative minor, the minor 6 (vi/i) adds a new color which would not normally be there within that modulation.

Also, since the minor 7th chord is not a diatonic i chord in harmonic minor, most jazz players will sub the minor 6th chord from melodic minor instead of using the min/maj7 found within harmonic minor.