Dec 5, 2009

An introduction to Inversions

I spoke of intervals in the previous article. I will explain inversions in this article. A firm understanding of these concepts will help in grasping harmonic principles much better.

Take the interval from C to E. This is a major third interval. 
What about the interval from E to C? Applying the principles of the previous lesson tells us that it is a minor sixth. 

The second interval is an inversion of the first. 

Consider F to Bb - a Perfect Fourth.
And Bb to F - This is a Perfect Fifth.

To help in doing a quick math of this, the way it works is as follows:
An interval and its corresponding inverted interval always add to 9. (Inversion of 3rd is a 6th, inversion of 4th is a 5th), A major interval inverted becomes a minor interval. A perfect interval remains perfect, and a diminished interval inverted becomes an augmented interval - as simple as that. 

Take a quick exercise to figure if you got it right. What is the inverted interval of
1) Major Second
2) Major Sixth
3) Augmented Fourth
4) Perfect Fifth

While the harmonic relevance of this is not immediately relevant, get it in clearly. Trust me, it is important.
This has been one short article - I wrote it while I was waiting for a flight in the airport on Free Internet :)

In the next article, I step into chords. Did I hear you say "At last!!". Patience, my friend.

2 comments:

Xoi said...

Do you mind helping with this one?

If you have an interval of C-Sharp and D.. what kind of interval would that be? Minor, Second, or Diminished?

It look like this:
http://i47.tinypic.com/so0bis.jpg

Rajesh said...

That would be a minor second. C to D or C# to D# would be a major second.
And diminished second doesn't exist.