Perfect fifths and such, confusing.

[KonKossKang]

https://www.teoria.com/en/tutorials/chords/06-const.php
5 semitones up/down finds the second note of a three note chord, going back to root then counting 5 whole notes up/down is the 3rd note it seems.

So basically that huge chord list I found earlier on was really not necessary since it seem like learning how they would form is actually faster than memorizing just the chords after all. Each chord even seems to stay in the scale too.
This stuff is actually pretty useful when it's sorta understood but still.

For some reason counting the same number of notes each way always finds the exact chord, even if it's a randomly chosen note to find a chord for.

D/F#/A, C/E/G, E/G#/B etc always finds the exact chord for them things. This website has no "why it's like that" section
ALSO, wtf also...

"Dominant seventh" chords always have this formula going on.
From first note to second note of those types of chords is always 5 semitones. Then from the second note of THOSE, 4 semitones. Then the third note of those chords is 4 semitones to the last note of the dominant 7th chord on that website.
The patterns are simpler than I thought, I think. One example is this Dominant 7th chord from teoria:
D/F#/A/C For them types it always go like that, the 3 note chord formula never work on the 4 note chords vice versa

 

[bandcoach]

sorry, you are wrong again

going up/down 5 semitones will not take you to a 3rd away from the note - that is a perfect 4th

if you count up 5 notes you will reach the perfect 5th/diminished 5th above the root

if you count down 5 notes you will reach the perfect 5th/diminished 5th below the note

examples in the key of C

Root Note	5 notes above	interval	5 notes below	interval
C	G	P5	F	P5
D	A	P5	G	P5
E	B	P5	A	P5
F	C	P5	B	d5
G	D	P5	C	P5
A	E	P5	D	P5
B	F	d5	E	P5

however, if you count up/down 3 notes and up/down 5 notes only in the one direction then your plan works

Starting Note	up 3 notes	5 notes above	Chord	intervals	down 3 notes	5 notes below	Chord	intervals
C	E	G	C	M3+P5	A	F	F	M3+P5
D	F	A	Dm	m3+P5	B	G	G	M3+P5
E	G	B	Em	m3+P5	C	A	Am	m3+P5
F	A	C	F	M3+P5	D	B	Bmb5	m3+d5
G	B	D	G	M3+P5	E	C	C	M3+P5
A	C	E	Am	m3+P5	F	D	Dm	m3+P5
B	D	F	Bmb5	m3+d5	G	E	Em	m3+P5

 

[bandcoach]

about semitone formulae

triads
major ~ 0-4-7
minor ~ 0-3-7
augmented ~ 0-4-8
diminished ~ 0-3-6
sus4 ~ 0-5-7

7ths
maj7 ~ 0-4-7-11
maj7#5 ~ 0-4-8-11
maj7b5 ~ 0-4-6-11
7 ~ 0-4-7-10
7#5 ~ 0-4-8-10
7b5 ~ 0-4-6-10
m7 ~ 0-3-7-10
m7#5 ~ 0-3-8-10
m7b5 ~ 0-3-6-10
min-maj7 ~ 0-3-7-11
min-maj7#5 ~ 0-3-7-11
min-maj7b5 ~ 0-3-6-11
diminished 7 ([sup]o[/sup]) ~ 0-3-6-9

 

[KonKossKang]

Thanks for clearing that up, I'll research the P5/d5 thing in the table on wiki later on though.
Hm...I see another pattern now for 3-notes.
0 seems to always be the root note.
Number after root note always seem to indicate major or minor.
Third note seems to always indicate a diminished or augmented signal note. 8 always has augmented but 6 always diminished.

The 4 note one is harder, but Ima take a crack at it.
0 root, like the 3 note formula and any other formula from that teoria website with the improved gui.
11 always has major in it, minor always has less than 10[ when it comes to 4th note]
if third note in 4 note chord's a 7 or 8 always looks like major will be added to that label bandcoach put on them.

I think Ima have to read some more of that website, I actually kinda understand alittle bit of that lol.

 

[bandcoach]

Thanks for clearing that up, I'll research the P5/d5 thing in the table on wiki later on though.
Hm...I see another pattern now for 3-notes.
0 seems to always be the root note.
Number after root note always seem to indicate major or minor.
Third note seems to always indicate a diminished or augmented signal note. 8 always has augmented but 6 always diminished.

0 is the root note
3 is minor 3rd
4 is major 3rd
5 is sus4
6 is diminished 5th
7 is perfect 5th
8 is augmented 5th

The 4 note one is harder, but Ima take a crack at it.
0 root, like the 3 note formula and any other formula from that teoria website with the improved gui.

0, 3, 4, 5, 6, 7, 8 are as above (they don't change simply because there are more notes)

11 always has major in it, minor always has less than 10[ when it comes to 4th note]

11 is major 7th ~ used with any major (0-4-X) or minor triad (0-3-X) or diminished triad (0-3-6) or the sus4 (0-5-7)
10 is minor 7th ~ used with any major (0-4-X) or minor triad (0-3-X) or diminished triad (0-3-6) or the sus4 (0-5-7)
9 is diminished 7th ~ only used with the diminished triad (0-3-6)

if third note in 4 note chord's a 7 or 8 always looks like major will be added to that label bandcoach put on them.

um no - 7 and 8 are referenced as perfect 5th or augmented 5th - they do not change their function from triads

if trying to determine underlying triad function you need to look at the first 3 notes in the 7th chord

however, the type of 7th does not influence the type of triad used as its building block (they are concurrent but not dependent)

I think Ima have to read some more of that website, I actually kinda understand alittle bit of that lol.