Chord Theory

Perhaps this will help
https://www.guitarnoise.com/article.php?id=508

You're dead on about the scale formula - those are the distances between scale tones. But here's where it gets you confused: any chord is built from the scale of the chord's root, not the scale of the key.

So let's say you're in the key of E (those frets on the open sixth string):

E-F#-G#-A-B-C#-D#-E

And you decide to play an F# chord. The notes in the key of F# would follow that interval pattern, but starting from F#:

F#-G#-A#-B-C#-D#-E#-F#

The F# major chord would use the 1st, 3rd, and 5th from the F# scale:

F#-A#-C#

The A# note isn't in the key of E.... so the F# chord doesn't occur in the key of E.

Now if you want to play chords in key, you'd take every other scale step in the key - in the key of E, starting from F#, you'd get:

F#-A-C#

which is F# minor.

greybeard:
Thanks a lot, your lesson really helped me understand.

Now I just have to study the notes and not just use the math. :lol:

NoteBoat:
Thanks are in need to you as well, your post reinforced my knowledge and gave me confidence that I was understanding this correctly.

Just to make sure I am understanding this right, I want to post a quick example I did and you guys can tell me if I am right or not:

I want to find out what notes are in a D major chord. And I read someone that the major chord is made up of the 1st, the 3rd, and the 5th.

I needed to get the root note, or the 1st, D: (I just wanted to find a random D, so I went to the 5th fret of the 5th string because it is A played open, B at the 2nd fret, c at the 4th fret, and D at the 5th fret, correct?)

To get the 3rd of the major scale, I counted up 4 halfsteps: (So I played the 4th fret of the 4th string, because I decied to move up one string, which is actually 5 halfsteps, I needed to move down one halfstep, or one fret, on that string leading me to the 4th fret of the 4th string)

To get the 5th, I count up 7 halfsteps: (So I played the 3rd fret of the 3rd string, because I decided to move up two strings, which equaled 9 steps(B string counts as 4 halfsteps), I then needed to move down two halfsteps to get me to the 3rd fret of the third string).

So I ended up with this:
|---0---|
|---0---|
|---3---|
|---4---|
|---5---|
|---x---|

It sounded ok, but it sounded better played:
|---0---|
|---0---|
|---4---|
|---4---|
|---5---|
|---x---|

Did I do anything wrong?

You made two mistakes...

First, counting up 7 half steps from D should get you to A (from 5th string 5th fret, you should get 5th string 12th fret... which = 3rd string 2nd fret, not 3rd)

Second, chords are composed using ONLY notes in the chord - the open first and second strings are E and B; your chord tones are D, F#, and A - so the open strings don't belong.

You'd get a D major with this:

x
x
2
4
5
x

The chords you have are:

D, F#, A#, B, E, which is 1-3-#5-6-9 in the key of D, which is D6/9+

and:

D, F#, B, B, E, which is 1-3-6-9 in the key of D. In guitar chord voicings, the '5' is optional (especially if you have at least four different notes played), so this would be a D6/9 chord.

NoteBoat:

Thank you very much, I was counting halfsteps using the math way and after looking at the chromatic scale I see that A is 7 halfsteps away from D.

Then I took the G string and moved up 2 halfsteps. :lol:

Thanks a lot, for your time and advice. It may it simple and annoying for you but it is greatly helping me.

Previously my only knowlege of theory was knowing what a chord is and what a scale is.

I know there is a ton more to learn (hopefully one never stops learning) but this new knowledge is really helping me shape "the big picture". Before when I would try to learn some theory I would focus just on the one subject and if I didn't understand it, it would lead me to think that if I can't even understand basic theory, how am I going to learn all the complex stuff which would lead me to stray from theory. But this is boosting my confidence and I hope to continue to study theory every day.

So once again, thanks a million! :lol:

The slight mistake, in your calculation, was that the adjustment comes when crossing the 3rd/2nd string divide. The B string is tuned 4 semitones up from the G, so that 's where the change comes. Other than that you're doing well.
There's a small typo in Noteboat's last post, which may confuse you. He wrote "Second, chords are composed using ONLY notes in the chord " - what he meant to say was "Second, chords are composed using ONLY notes in the scale".

A basic chord consists of the root, 3rd and 5th - but they can occur more than once. Take the G chord (320003 - GBDGBG), you've got the root (G) 3 times, the 3rd (B) twice and the 5th (D) only once. If an open string isn't a note that is part of the scale, you either have to fret it (and make it a scale note - root, 3rd or 5th) or not play it (you can mute it, if it's in between other scale notes).

greybeard:
Thanks for the clarification. :lol:

When I figured out the three notes to play I wondered if I just play those three, then I reflected on a lot of the chords I know that play the rest of the strings open, so I just played it with the remaining strings open. Now I see that that every string must be fretted to (or open to) a note in that scale.

Now I see that that every string must be fretted to (or open to) a note in that scale.

That's a note in the chord, Nexion, not just the scale.

NoteBoat's and Greybeard's point, (as I'm sure they'd point out if they were around at the moment) is that having found your three chord notes (e.g. D F# & A) on three strings, the other strings(whether fretted or open) must duplicate any or all of those three chord notes only, (or else be omitted). You can't play any notes other than the chord notes or you will end up playing a different chord completely, as your ear told you when you added the open B and E strings to your D chord. Although both were scale notes, they're not notes of the D major chord, so adding them will give you a chord that consists of D F# A B & E, (D6 added 9th, if you're interested. (D6/9)).

Rereading fretsources answer, I think that Noteboat was trying to make the same point - sorry for the misunderstanding.

oops - I just noticed NoteBoat already named that chord as D 6/9+
Must pay more attention :oops:

Now I see that that every string must be fretted to (or open to) a note in that scale.

That's a note in the chord, Nexion, not just the scale.
Yeah I understand that, I meant to say chord.

But thanks for the continuing support and advice!

what I think would help you out a lot is if you learn the names of the notes on the fretboard. then instead of counting intervals you'll be saying the note names.

That's my next move.