Good morning everyone,
I have a question regarding the blues chord progression for a bebop-style blues.
Let's take C as our key in question
|C7 |F7 |C7 |Gm7 C7|
|F7 |F#dim|C7 |Em7 A7|
|Dm7 |G7 |Em7 A7|Dm7 G7|
Bar 1 is clearly in the key of C. Bar 2 is clearly in F7.
Bar 4, the ii-V is relative to the F in Bar 5 (thus the ii-V-I is the Gm7-C7-F7)
My question is this: Are the Em7 and A7 in bars 8 and 11 drawn exclusively from the key of C?
Because A7 = A, B, C#, D, E, F#, G, A
If it were drawn from C, there would be no #s at all.
I have been working on my blues but something isn't quite right.
a) Does my question actually make any sense
b) Anyone have an answer?
First, your question does make sense because it is so often asked and the premise is based upon faulty Teaching of music theory in general (even at the college level).
Do I have an answer --- (Hummm, we'll see).
The first issue is "keyness". What makes a piece of music be in the key of C major or C minor or F# whatever? To be honest, it is incapable of being quantified (which is the purpose many have made of music theory -- to define the un-definable).
We can look simply at an iconic piece of music -- Beethoven's 5th -- and see it. We accept that it is in C minor (that's what they put in every catalog -- "Symphony no. 5 in C minor.) Well it begins with 4 notes (you supply the rhythm) G G G Eb F F F D, which spells the key of Eb major as well as anything else. AND it ends in C Major. In the process, more time is spent in anything but C (major or minor) than in that key! Yet, we at least accept that it is in C.
That digression aside, "keyness" is a process of proving that one note and related harmony is THE point of rest. The harmonic musical journey is that of in some way starting from that point of rest (though we may wake up restless) and ending up in the one place that we can feel totally comfortable and call home.
In reality, all keys have a potential of being chromatic -- any available note can be used whether or not it is in the scale of that key. Just because the C major scale is C D E F G A B C, does not mean that C#, D#, F#, Bb, etc. can't be used. All we have to do is prove that "C" is king.
BUT, these scale steps are important. They represent a certain direct relationship to C. F & G are related to C by a 5th, a strong relationship (G and its harmony being generally more important to establishing C than C itself.)
Before I do too much philosophizing, we can look at the blues line and see that, except for the F# dim, the bass line is totally diatonic (related to the scale) of C. In the end, most tonal western music is held together by the bass and regardless how wild and chromatic the upper voices get, the bass is the ground that proves that no matter what, all is right with the world.
So the bass is:
|I |IV |I |V I |
|IV |#IV |I |III VI|
|II |V |III VI|II V |(I)
All of which can be logically (as far as musical logic goes) be accepted as C major for I. The relationships between these roots indicate nothing other in our tonal system. And yet in this progression, amongst all of these chords, there are more non-C chords than C chords.
This was a long way around to show that key and scale (and other factors of music) are not always directly related.
Scott