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Paul McCartney has created some unusual but harmonious progressions using this musical device
PHOTO BY CHRIS PUTNAM/FUTURE PUBLISHING VIA GETTY IMAGES
Not all chord progressions stay strictly within the diatonic/chord scale convention – and that’s a good thing. Taking a little look at the theory involved here, the C major diatonic/chord scale is Cmaj-Dmin-Emin-Fmaj-Gmaj-Amin-B diminished (Bm7 b5 is also commonly used). These are often numbered sequentially using Roman numerals, so a II-V-I progression in C translates as Dm-Gmaj-Cmaj and so on. The ‘resolve’ from V to I in a chord progression is a very popular move. Let’s embellish it a bit and say the V is a V7, short for dominant 7 – namely a V chord with the b7 added. In C, G7 is the dominant (V7) that resolves to Cmaj (I).