Introducing flattened thirds and sevenths adds colour and excitement to a tune; but it's also interesting to throw sixths and ninths into your improvisations.
Listen to a great creative player such as Shaye Cohn and note how frequently she gives a lot of emphasis to 6ths and 9ths - especially at the start of one of the final choruses, when she is still finding fresh approaches. For example, a tune may begin with two bars firmly on the C major chord but you may find Shaye decisively hitting several 'A's (the 6th). Or in a tune beginning with the D major chord, she will deliberately and firmly go for the 'E' above the chord, making a 9th.
Listen to a great creative player such as Shaye Cohn and note how frequently she gives a lot of emphasis to 6ths and 9ths - especially at the start of one of the final choruses, when she is still finding fresh approaches. For example, a tune may begin with two bars firmly on the C major chord but you may find Shaye decisively hitting several 'A's (the 6th). Or in a tune beginning with the D major chord, she will deliberately and firmly go for the 'E' above the chord, making a 9th.
Composers have been well aware of the effect gained by making the sixth or the ninth the melody note at a particular point, too.
Think, for example, of You're The Cream in My Coffee played in the key of C. You find many of the melody notes are D played above a C major chord, or A played above a G chord.
Or take There'll Be Some Changes Made played in the key of C. What do you find? Lots of Bs above the A chord, and plenty of Es above the D chord.
Another is If I Had You: Think of it in the key of Bb. Numerous times in this song, you find (yes - in the composed melody) a C being played above a Bb chord. You find a G being played above an F7th chord. And you find Cs being played above Eb chords.
I'm Crazy 'Bout My Baby is another. Its Middle Eight is unusual, its special effect being achieved by the fact that the melody notes are so often the 6ths or the 9th of the chords.
Effective, isn't it?
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Reader Barrie adds:
Another is If I Had You: Think of it in the key of Bb. Numerous times in this song, you find (yes - in the composed melody) a C being played above a Bb chord. You find a G being played above an F7th chord. And you find Cs being played above Eb chords.
I'm Crazy 'Bout My Baby is another. Its Middle Eight is unusual, its special effect being achieved by the fact that the melody notes are so often the 6ths or the 9th of the chords.
Effective, isn't it?
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Reader Barrie adds:
Hi Ivan,
I agree with your statement about using a 6th and a 9th. I use the 6th a lot, a very useful note. At times it can be sustained over several chords. I mainly use the 9th on the fourth bar of a 12 bar blues. It works well.