Blues Scale and Chords?

This tip influenced by jbooth12...

Should you play ONE blues scale (they key of the song - G Blues Scale if you're in the Key of G) over all of the chord changes... or play a blues scale based on the starting note of each chord (C Blues Scale for the IV7 Chord and a D Blues Scale for the V7 Chord)?

Good question... you can do either. For example... if you're in the key of G on a C Harmonica (2nd Position) you can use a G Blues Scale over ALL of the chord changes. This works well and is done most of the time... this is the way to start. Next, try playing the G Blues Scale on the I7 Chord, C Blues Scale on the IV7 chord and D Blues Scale on the V7 Chord. This is also done all of the time to good effect.

What do I teach?

I teach to use the G Blues Scale all of the time (G Bb C Db D F G = 2 3' 4+ 4' 4 5 6+), BUT, when on the IV7 Chord (C E G Bb = 1+ 2+ 2 3' 4+) emphasize the notes from the IV7 Chord Blues Scale already found in the G Blues Scale, which are the notes C Bb G (4+ 3' 2). Do the same for the V7 Chord (D F# A C = 1 2' 3" 4+ 4), using the D F G (6+ 5 4) of the V7 Chord Blues Scale. To try this, try soloing using the notes below...

I7 Chord = 6+ 5 4 4' 4+ 3' 2
IV7 Chord = 4+ 3' 2
V7 Chord = 6+ 5 4 (If you're going to hold any of these notes make it 4)

Make sure to use a bluesy jam track, like the one found in Bending Study 4, "My Blues."