Blues Scale Notes - major 6th?

Question

I've typically always played a blues scale in C as:

C Eb F Gb G Bb

However, in a book I'm reading, the author lists the blues scale for C as:

C D Eb E F Gb G A Bb

Improvising over this new scale definitely gives me a more full sound, and I can get a sense where the second and major third fit in - however, the A always sounds like it takes the sound away from bluesy. Are major 6ths typically only used as passing tones when playing the blues, or should I focus more on this when the harmony shifts from I to IV or V?

Answer 1

What people usually mean by "blues scale" is the scale that you already knew, i.e. a minor pentatonic scale with an added b5 ("blue note"). What the author of that book refers to as blues scale is actually more like a collection of notes, all of which can be used over a blues progression. The difference with the standard blues scale is that not all of those notes will sound equally good over all three basic chords of the progression (I7, IV7, V7).

With the standard blues scale, even though some notes are pretty dissonant over some chords, none of them sounds really wrong to our ears in a blues context. Even the b5 can always be played as a passing tone. However, the other scale contains notes that would sound really wrong (if played as target notes) over certain chords. E.g. the note E simply sounds wrong over the IV7 chord (F7) because it clashes with the b7 of that chord (Eb), and not in a bluesy way but in a bad way.

There are two ways how you can understand that collection of notes referred to as "blues scale" by the author. It can be seen as the union of the notes of the standard blues scale and the notes of the major pentatonic scale:

blues scale: C Eb F Gb G Bb

major pentatonic: C D E G A

=> C D Eb E F Gb G A Bb

Equivalently, you can arrive at those notes by filling up the C mixolydian scale with the two blue notes from the blues scale (the b3 and the b5):

C mixolydian: C D E F G A Bb + Eb Gb => C D Eb E F Gb G A Bb

Again, I wouldn't actually call those notes a scale, because there is no chord over which you can really play that scale. They are rather a collection of notes all of which can be useful at a certain moment in a blues progression. But then you could as well write down the chromatic scale and call it a blues scale, because if you know how to, you can play all 12 notes and make them sound good over a blues progression.

To answer your question about the major 6th, the A in the case of C major: it is not only a passing tone, it actually can be used over all 3 chords. Over the one it is a 13, over the IV it is the 3rd, and over the V it is the 9th. One way to use it, is to distinguish the I from the IV in your solo: you could play some motif over the I containing a Bb (and no E, because this won't work over the IV). Then you repeat that motive over the IV chord, but you exchange the Bb for the A. In this way you make the transition from I to IV very clear. But that's not the only use of the major 6th, because - as mentioned before - it is a valid tension for both I and V chords as well. One example: Larry Carlton start his solo over BP blues on the major 6th (he bends to it from the 5). Check it out here.

Answer 2

Two blues scales exist generally. Minor blues as in C, Eb, F, Gb, G, Bb. Major blues as in C, D, Eb, E, G, A. Often players will mix the sets of notes in their playing.

The minor blues is probably used more in guitar playing, due to the pattern of notes easily found because of the way guitars are tuned. The whole solo in Stevie Wonder's Sir Duke is major blues.

The E serves well to sweeten up a line over a C chord; the A works the same over an F chord. I've often wondered what happened to B to go over the dominant G chord.

After all this, any of the twelve notes can fit into a blues (or any other) song. Using the blues notes from ,say, C work over C, but when the chord changes to F, the F blues notes will fit well. Of course, some are the same, but others have a better fit. As in there's no F in C blues, but it's there in F blues: and works well over an F chord!

So, over a typical three chord blues, particularly a major blues, any of the notes from Cmaj/min;Fmaj/min;G maj/min blues scales could be used. That covers, at a guess, all available notes! One wouldn'd use an E over C minor, etc, though.

Answer 3

The problem with answering the question "what notes are in the blues scale" is that the archetypal bluesy sound comes from bending and inflecting the notes within certain ranges, so any attempt at defining a blues scale in terms of the 12-note scale is only going to be an approximation.

When soloing, I personally play the blues scale on the guitar as a pseudo-pentatonic something like this:

• C

• a whole range of notes around Eb, covering the range down to D and up to E.

• F, bending up a little (maybe not as far as Gb)

• G

• Bb, with scope to bend up a little (but maybe more like a quarter tone - not as far as B)

So I don't personally play it with an A in. However, Blues is often about finding "the space between", and I wouldn't deny that with all that flexibility I've outlined (which already allows some major tonality) for that you couldn't add the A and move a little more towards major.

When you get a chord change to F or G (from tonic C) in blues, it's often much more like a transposition to F or G, so you are shifting your whole scale around, not just changing the chord; and yet there are often nods to western harmony too. Again, the space between!