Trouble understanding the CAGED chord shapes

Question

I'm someone who has been working in several different fields since a decade, such as BPO, Accounting and lately going into programming. I have always admired music through numerous songs throughout my life so far. I always had this thing that I want to be able to play atleast one instrument in my life. So last week I bought a guitar. But I have no sense of what goes behind making the songs. So I decided to learn the basics of music theory and I got to know what notes, sharps and flats are. Little bit about triads and diatonic chords.

But what I don't understand is the chord shapes or the CAGED shapes. Can someone explain how those are made/drawn? There must be some logical explanation for them. Like how it's determined that a certain string are to be muted, certain to be played open. Taking A major chord's instance, how has it been decided that the 6th string will be muted, 1st and 5th strings to be played open and why the E, A and C# are played on the 2nd fret while there are other many frets that have those notes, why only the 2nd one? I have no problem with their design or something but I want to understand how they came into picture the way they are. Please help as I'm overwhelmed by the chord shapes.

Answer 1

There are other ways to play an A major chord on a guitar, for instance with a barré on the 5th fret (looks like an open E major chord shifted five semitones up). The one you're describing is just one of them. It's the one that's most common, simplest and easiest to play, but if you're going for a particular sound effect (or for easier change to, say, a G# chord coming next), you can choose any other. Want to put those three fingers to the 14th fret instead? With or, if you want to play something very weird, even without a barré on the 12th? You certainly can.

The A major chord consists of tones A, C# and E. This is non-negotiable. It's the definition of an A major chord.

Also as a rule, a guitar chord starts with its root tone (in case of A major, an A) on one of the lower three strings (E6, A, or D). You strum from this string on, skipping the ones that come before.

Other than that, your hand's the limit. You can't hold one string on the second fret and the next on the fourteenth because it's physically impossible.

Any position of the left hand that results in a "starts with the root, all strings played give a tone from the chord, and all tones in the chord are represented" situation is valid.

The common open A major chord has:

string E6: not played
string A: open, plays A (the root)
string D: 2nd fret, plays E
string G: 2nd fret, plays A
string B: 2nd fret, plays C#
string E1: open, plays E

Starting with an A, the tones included are all A, C# and E, which is what makes an A major chord an A major.

The "barré on 5th fret" version of A major gives you:

string E6: 5th fret, plays A (the root)
string A: 7th fret, plays E
string D: 7th fret, plays A
string G: 6th fret, plays C#
string B: 5th fret, plays E
string E1: 5th fret, plays A

As you can see, this is also a perfectly good A major chord.

Answer 2

Sort of two questions in one here. So here goes.

The CAGED system is born from the open chords playable on guitar. Those are surprise surprise, C, A, G, E and (I'm a bit sceptical) D.

Taking those shapes which all produce chords which include some open strings, as they stand, the shapes themselves can be moved up the fingerboard, with a barre finger taking the place of the nut, where the open strings vibrate from.

So, as an example, open C shape makes, obviously, C. Move up to 3rd fret barre, use an A shape, and it's another C. Move to 5th fret barre again, with pinky on fret 8, using a G shape, it's another C. Move the barre up to fret 8, and use an E shape, there's another c chord.

As far as the other part is concerned, let's take an open C shape. There will be only 3 notes played, in different octaves as well. C, E and G. The order doesn't really matter, nor how many of each.

BUT - a lot of guitar sites insist on chords being played in root position that is with the C as the lowest note. Hence the fattest string gets muted. However, that bottom string, could be left open (E), and included, quite legitimately, in the chord. Likewise, it could be fretted on 3 (G) and be played just as well. Or - top string could be played on 3rd fret (G) instead of the open (E), for a different voicing, which is permissible too.

There are more advanced chords which, on guitar, necessitate muting certain strings, but that's for another day.