You’re wrong about m7sus4… Consider the progression C, G/B, Am7sus4, Am. It would be illogical to notate it with roman numerals like: I, V, VI7sus4, vi
Obviously, the 7sus4 chord implies the vi (=minor) function and not the VI (=major) function in this case, hence m7sus4 and not 7sus4.
I would argue that in this case the chord you have named as ‘Am7sus4’, should be named ‘A7sus4’ because it has no minor third in it, although it could still be considered to be a somewhat minor chord because of the 10 semitone, minor seventh interval ( A to G ). Technically the full chord name is ‘A Dominant 7th, suspended 4th’… A D E G [0 5 7 10] [root, P4, P5, m7] [1st, 4th, 5th, b7th]
Sorry about the E-A-D-G confusion… It could be a number of things, or none at all. Em7add11no5 is one possibility. The add11 note is the A in that case, so I don’t get what you’re talking about.
I would like to point out that in the case of the ‘E A D G’ chord, I did specify three times that the ‘A’ had not been moved up an octave whilst the ‘G’ had been. The chord written with octave numbers alongside would be ‘E4 A4 D4 G5’. ‘E’ to ‘A’ could not have been an 11th interval ( or in other words, from ‘E’ to the 11th scale degree of the E Major scale ) because it had not been moved up by one octave.
The ‘E’ to ‘A’ interval in that chord is clearly a Perfect 4th interval ( P4 ) because the ‘E’ and the ‘A’ are within the same octave. I dont beleive that ‘Em7add11no5’ is the correct name for that chord.
The ‘Em’ part of the chord name implies that a minor 3rd is present within the interval structure of the chord. There is no minor 3rd.
The ‘add11’ part of the chord name implies that there is an 11th interval in the chord. There is no 11th interval.
‘Sus4’ was not included in the chord name but there is clearly a perfect fourth interval in the chord ( replacing the minor 3rd ).
Presumably the ‘no5’ part of your chord name refers to the position from which to play the chord as a guitar chord.
I understand your argument that chords made up of the same notes can sometimes be named differently depending on their function, as in the ‘C6’ and ‘Am7’ example, but consider this:
All chords are named, not according to their function, but with reference to the scale degrees of the Major scale of the chords root note.
Here is the ‘C6’ chord from your example :
C6 = C E G A [0 4 7 9] [root, Major 3rd, Perfect 5th, Major 6th]
[1st C, 3rd E, 5th G, 6th A] <- The chords root note is ‘C’. It contains the 1st, 3rd, 5th and 6th scale degrees of the C Major scale ( 1C 2D 3E 4F 5G 6A 7B ).
Here is the ‘Am7’ chord from your example :
Am7 = A C E G [0 3 7 10] [root, minor 3rd, Perfect 5th, minor 7th]
[1st A, b3rd C, 5th E, b7th G] <- The chords root note is ‘A’. It contains the 1st, flattened 3rd, 5th and flattened 7th scale degrees of the A Major scale ( 1A 2B 3C# 4D 5E 6F# 7G# ).
If the scale you are working in is a Major scale, it should generally hold true that:
I chords are Major
ii chords are minor
iii chords are minor
IV chords are Major
V chords are Major
vi chords are minor
vii chords are diminished
However, if the scale you were working in was ‘C diminished’, there are 8 scale degrees.
If I took the 1st scale degree and made a chord that was not a Major chord, the intervals in the chord would still be described with reference to the scale degrees of the C Major scale. The chord name itself describes the interval structure compared to the scale degrees of the C Major scale.
C diminished ( whole-half ):
1C 2D 3D# 4F 5F# 6G# 7A 8B ( renoise scale spelling )
1C 2D 3Eb 4F 5Gb 6Ab 7A 8B ( traditional / classical spelling )
Cdim: C D# F# [0 3 6] [m3 dim5] [1 b3 4] [R : 1 3 5] [L : 5 3 1]
[1st C, b3rd Eb, b5th Gb : 1C 2D 3E 4F 5G 6A 7B]
Its function seems to be ‘tonic’ ( I ) but it is not a Major chord.
Maybe the diminished scale starts from vii? I don’t know.
Makes me wonder about the modes.
Here is another example :
What about ‘Asus2sus4’? It comes from the sixth scale degree of the C Major scale, ‘A’ ( vi - submediant ), but it has no minor intervals at all. Surely it can not be named as ‘Amsus2sus4’ just because it comes from the sixth scale degree of the C Major scale, ‘A’ ( vi - submediant )?
Asus2sus4: A B D E [0 2 5 7] [root M2 P4 P5] [6 7 2 3]
[1st A, 2nd B, 4th D, 5th E : 1A 2B 3C# 4D 5E 6F# 7G#]