13

So, I'm learning 'Stray Cat Strut' right now and came across something I'm not sure I understood. I have to say, I've only just begun to learn theory, so maybe that's why.

Anyway, as far as I can tell, the song is in the key of Cm and the intro chords are: Cm - A# - G# - G7.

While the Cm, A# and G# chords are all built from notes that are in the scale, the G7 contains a B, which is not in the scale.

Why is it used then? Could it be, because it's the major 7th, creating tension, striving to resolve etc. or is there another reason?

Also, how does this out-of-scale chord affect the chord progression? Is it: i - VI - V - IV7 ?

Or would you have to write that in a different way then?

2 Answers 2

19

Why?

  • It sounds good.
  • Music would sound boring after a while if all you played were the notes in the scale.

I would be hard-pressed to find music that doesn't have notes outside of the scale--scales are just the basis for melodies, and the home base from which you can stray in creative ways.

In this particular context (and your chords would be better written as Bb and Ab, since there are no sharps in the C minor scale), the chords being played are:

i  - bVII - VI - V7
Cm - Bb   - Ab - G7

The 3rd of the G7 is B natural, which is the leading tone of C minor. Keep in mind the minor scale very commonly alters the 6th and the 7th -- the harmonic minor scale would use the flat/minor 6th (Ab) and the major 7th (B nat) anyway, and the melodic minor scale keeps them major on the way up and minor on the way down.

The main reason is that G7 is the dominant 7th chord. In a typical cadence or resolution, the dominant 7th chord resolves to i, with the bass note moving down by a fifth, from G to C, in a standard V7 - i progression. The V7 chord has dominant function because the 3rd and the 7th of that chord lead directly to the root and third of the i chord.

7
  • 1
    Thanks for explaining this in such great detail. I actually learned much more then what I asked ^^ Oct 27, 2012 at 21:12
  • More commonly I have seen G minor 7th with a Bb in C minor pieces because most are in natural minor or aeolian.
    – Caters
    Oct 8, 2014 at 1:17
  • 1
    @caters I would disagree. At least in the context of western classical music known as "common practice" harmony, the dominant 7th chord is tremendously important and appears this way in both major and minor key signatures. Modal harmony (natural minor/aeolian) is not what we would call common practice.
    – NReilingh
    Oct 8, 2014 at 1:31
  • Beethoven's 5th symphony, Natural minor. Lots of other C minor pieces, Natural minor.
    – Caters
    Oct 8, 2014 at 1:55
  • @caters Beethoven's 5th is full of B naturals used in V7 chords.
    – NReilingh
    Oct 8, 2014 at 2:03
0

Generally, and in this case, the note which doesn't appear to fit is part of the progression into the next chord and sequence.

Chords give you the baseline for the song but the melody doesn't need to match closely, or at all!

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.