The topic here was / is INTERVAL INVERSIONS.
When necessary, I refer to the chart below.
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Semitones Interval
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0 ... Unison
1 ... flat 2nd
2 ... 2nd
3 ... minor 3rd
4 ... major 3rd
5 ... perfect 4th
6 ... flat 5th (diminished 5th or augmented 4th)
7 ... perfect 5th
8 ... minor 6th (or sharp 5th/augmented 5th)
9 ... major 6th
10 .. minor 7th (flat 7th)
11 .. major 7th
12 .. octave
13 .. flat 9th
14 .. 9th
15 .. sharp 9th/minor 10th (just minor 3rd one octave higher)
16 .. major 10th (just major 3rd one octave higher)
17 .. 11th
18 .. augmented 11th
19 .. perfect 12th (octave above perfect 5th)
20 .. flat 13th
21 .. 13th
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1 ... flat 2nd
11 .. major 7th
2 ... 2nd
10 .. minor 7th (flat 7th)
3 ... minor 3rd
9 ... major 6th
4 ... major 3rd
8 ... minor 6th (or sharp 5th/augmented 5th)
5 ... perfect 4th
7 ... perfect 5th
6 ... flat 5th (diminished 5th or augmented 4th)
6 ... augm 4th (augmented 4th or diminished 5th)
... and the cheese stands alone with the tritone!
.....
Or better yet a minor 7 becomes a Major 6th ... What ?
Eminor7 = 1,b3,5,b7 = E,G,B,D
G Maj 6 = 1,3,5,6 = G,B,D,E
I think this is what you meant ... a chord inversion :)
.....
4 frets down from a Maj 6 is a min 7th or relative minor ... What ?
... again, using my 'homeschooled' chart above,
this is what I came up with.
9 ... major 6th
(9 minus 4)
5 ... perfect 4th
I don't see how this links to a [ a min 7th ]
... or relative minor ... What ?
G Maj 6 = 1,3,5,6 = G,B,D,E
4 frets down I have Eb,G,Bb,C
How is that a 'RELATIVE minor' ?
I go 3 frets down and play:
E,F#,G,A,B,C,D = E Aeolian
Help me understand ... and welcome back.