Wednesday, October 14, 2009

Guitar Chord Progressions and Secondary Dominant Major 2 Chord

"Why do some guitar chord progressions have a major second chord when it should be minor? What is a secondary dominant?"



If you know anything about guitar music theory you know that building chords from the major scale produces the following chord sequence:

1. I major
2. ii minor
3. iii minor
4. IV major
5. V major
6. vi minor
7. vii minor (flat five)


But songs with major two chords are fairly common on guitar. The songs listed below are just a few examples:

"That'll Be The Day"
Buddy Holly - Key of A but includes a B major 2 chord.
"Hey Good Looking" Hank Williams - Key of C but includes a D major 2 chord.
"Patience" Guns and Roses - Key of G (gtr. tuned down 1/2 step to Eb) but includes an A major 2 chord.
"Out of My Head" Fastball - Key of E but includes an F# major 2 chord.

A major 2 chord is actually a key change and stems from the music theory behind a functioning dominant seven chord. A dominant seven chord (which can be referred to as simply 7) is a major chord with a flat seven interval. This occurs naturally on the fifth scale degree in a major scale. The dominant seven 5 chord has a bit of tension that leads to and resolves on 1 (the 'tonic' in a major scale). For example, in the key of G a D7 chord leads to and resolves on G. D is said to be the 'dominant' of G major. In fact, D can lead to G whether or not the guitar chord actually has the seventh interval in it.

"Hey Good Looking" by Hank Williams is in the key of C and normally has a D minor chord, but the song uses a D major instead which creates a strong pull to G. When playing this song on guitar you're in the key of C but you're borrowing the dominant from the key of G in order to produce the dominant pull to and resolution on G. Get it? This is said to be a 'secondary dominant' chord and is a composition technique that can be used in any key. So the song examples I used can be explained like this:

"That'll Be The Day"
B major is the dominant of and leads to E.
"Hey Good Looking" D major is the dominant of and leads to G.
"Patience" A major is the dominant of and leads to D.
"Out of My Head" F# major is the dominant of and leads to B.

You can create secondary dominant movement for any chord in a key. Just remember that it's a type of key change so the scale you play over it with should follow. This is important when learning music theory for guitar.

3 comments:

Anonymous said...

Thanks Desi ; that was very helpful

mbon008 said...

Dear Desi,

What about the Chord Progression:

G major A major C major D major.
I --->II--->IV---->V.

Is the key:

G major with II (A Major)
or D mixolydian with 'II' instead of 'ii'
or

D major with bVII IV--->V-->bVII--->I(?)
G --->D-->C------>D

Or all of them depending on how you look at it? Would you agree G major key with II major (A) secondary dominant with tonal centre D is the best? or is the tonal center still G?

Example:
Song: Weak by Skunk Anansie.
Verse is: C-->D-->Em
Key: G major/Eminor
vi-->V-->IV-->vi
(relative minor, (vi) with regression (V-->VI)and deceptive (?) (IV-->vi) plagal cadence? HELP!

So much for analysing music! I'm off to play!

Thanks

Mike

Mr. Desi Serna said...

Michael,

G major A major C major D major can be thought of and played over in a few ways.

1. G and A are 4 and 5 from the key of D, C and D are 4 and 5 from the key of G.

or

2. The A chord is a key change, the rest is all in G (this is the more likely case).

In either case you have to switch parent major scales if you're going to play major scale patterns over the progression. Or you could try playing the G major scale and avoiding the C note so that it doesn't clash with the C# note in the A major chord. Or, simply raise the C note to C# (which changes the ii chord Am to A major). This changes the G major scale to G Lydian mode which is the D major scale. The A chord would be the 5th of D (mixolydian mode, a.k.a. dominant scale).

You'll have to experiment and decide which option sounds best to you. Let me know what you come up with.