If you've ever opened The Real Book and played Billy Strayhorn's jazz ballad, Chelsea Bridge, you've seen that the opening chords are Eb7(#11) and Db7(#11). Beautiful, yes. But if we listen to Strayhorn's original arrangement of the tune, for the Duke Ellington Orchestra, we hear different harmonies: Bbm6(maj7) and Abm6(maj7):
Duke Ellington: Chelsea Bridge
Either way, the chords are wonderful and very impressionist. But if you play the melody with both versions of the harmony, you'll hear a big difference. I myself learned the "wrong" chords and enjoyed playing it like that for years. Now, after getting accustomed to the Ellington and Strayhorn recordings of the tune, I come to prefer Strayhorn's original harmonies.
So why are the Real Book chord changes wrong? Well, the original, unauthorized version of the book was compiled by Berklee College of Music students, who initially put together the book for their friends and to make a little money to pay for their education. There were many mistakes in the original editions of the book. The newer, authorized editions of The Real Book have fixed many of these wrong chords but for some reason have left the Chelsea Bridge chords "as is."
That's fine, and now that you know what Strayhorn's original chords were, you can make an informed artistic choice for yourself!
Chelsea Bridge: Journey Through The Real Book #60
Enjoy the journey, and "let the music flow!"
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