Harmonically speaking, the odd thing about the blues compared to "white" folk music is that the blues are based on the major pentatonic scale of
the flatted third of the key of the song, not the major pentatonic scale of the key that the song is in. Thus a white folk song in A-major typically uses the notes from the pentatonic scale for A (A, B, C#, E,
F#), but a blues song in A-major uses the notes from the pentatonic scale for C (C, D, E, G, A).
Tahir: In other words, the A minor pentatonic scale. I think this is a crucial piece of information, because how it came about may well be that someone tried, either by accident or by design, to play a minor pentatonic scale over a major chord riff and found that it worked, in a strange kind of way. The flat five completes the 'diminished' type harmony and I guess that was probably a logical next step.
The crucial "blues" notes are the flatted third and the flatted seventh of the major diatonic scale of the key of
the song (e.g, C and G in the key of A).
We take this blues scale for granted nowadays, so it's easy to overlook
how different this is from white folk music. I know of no plausible historical explanations for this harmonic transposition up to the flatted third in blues music; I'm just happy it happened.
Tahir: See my guess above. What I'm pretty sure didn't happen is that it evolved in some direct way from work songs of the slavery days, as has often been suggested. Yes the call and response type of thing, which you find in blues, had that sort of origin, but that's obvious and trivial, since that is a characteristic of African music in general. I read an article recently about WC Handley and the first time he heard the blues. He was apparently on a station waiting for a train and a poor black man with a guitar near him (and dressed in rags) started playing this very strange music by sliding a knife on the strings. He recounted that it was like nothing he had ever heard before. As a black man who was already trained in classical music he realised that this was something different from both western harmony AND African folk music. For those of us who grew up in the post-blues era of rock music, other harmonies often sound relatively bland now.
-------------- next part -------------- All Email originating from UWC is covered by disclaimer http://www.uwc.ac.za/portal/public/portal_services/disclaimer.htm