Chord Theory: A chord

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But since the I, III, V constituents of an A major scales are A, C# and E, it is perfectly okay to play A as:

o------------------
---2---------------
---2---------------
X------------------
X------------------
X------------------

ya? Similarly, E major can be played as:

o------------------
o------------------
1------------------
X------------------
X------------------
X------------------

If so, is there a distinct advantage in playing A and E as we normally do rather than playing A as in case 2 and E as I tabbed just above?

Cheers

Major and minor chords consist of three notes in their basic triad form, the 1st, 3rd, and 5th notes of the major scale for Major chords, the 1st, flat 3rd, and 5th for minor. Your description of the A triad above is fine, and will sound a basic chord. Your E major chord is actually an inversion - 1st inversion I think with the G# being played as the lowest note. Again, fine as an alternate voicing of the basic triad.

Adding more notes by doubling up on certain notes in the triad give the chord more fullness. The standard A chord for example doubles up on the root - the A and the 5th - the E. Play the standard a chord sounding out all the notes, then play the simple triad and listen to the difference. Both are valid A chords, the triad just isn't as full as the standard chord.

Major and minor chords consist of three notes in their basic triad form, the 1st, 3rd, and 5th notes of the major scale for Major chords, the 1st, flat 3rd, and 5th for minor.

Almost - the A major chord uses the 1st, 3rd and 5th notes of the A Major Scale, and Am uses the 1st, 3rd and 5th notes of the A Minor Scale.

Sometimes you'll be ok with a three note chord, and sometimes you'll want all six strings - that's the only real difference IMHO.

Best,

A :-)

Almost - the A major chord uses the 1st, 3rd and 5th notes of the A Major Scale, and Am uses the 1st, 3rd and 5th notes of the A Minor Scale.

Actually, we're both right. You can construct the Am chord from the A minor scale using the 1st,3rd, and 5th notes:

A Minor Scale

A,B,C,D,E,F,G,A

1st,3rd,5th - A,C,E

Or you can construct the Am chord from the A Major scale using the 1st,Flat 3rd, and 5th notes:

A Major Scale

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

1st,b3rd,5th - A,C,D = Am
1st,3rd,5th = A,C#,D = AMajor

The results are the same. Just depends upon whether your working in a major or minor key.

Chord formulas are always made from the major scale, never the minor.

Oh, triads will work out the same due to mere coincidence... when you move beyond them into seventh chords and other extensions, you'll run into trouble forming chords from minor scales - because there's more than one minor scale!

Let's take Am7 for example:

Using the natural minor, it's 1-3-5-7
Using the melodic or harmonic minor, it's 1-3-5-b7

Things get worse with 13th chords. Is it 1-3-5-7-9-11-13 (the natural minor), 1-3-5-b7-9-11-13 (the harmonic minor), or 1-3-5-b7-9-11-b13 (the melodic minor?

To avoid having to specify the type of minor scale used, and having to remember which adjustments to make for each of the minor scales, we build all chord formulas from the major scale. A minor chord type will always be a b3 in the major scale, and the other notes (b7 for dominant, etc.) will always follow formula - because unlike the minor, there is only one major scale pattern.

...... when you move beyond them into seventh chords and other extensions, you'll run into trouble forming chords from minor scales - because there's more than one minor scale!

Excellent point. I hadn't bothered to think beyond simple triad construction. Thanks.

Thanks for all your inputs.

cheers