The substrate for the best American music is the blues (including van der Merwe’s broader notion of the “popular style”), even when the musician in question is a mid-20th century symphonist: note the variable third in the cello right from the start of Roy Harris’s Symphony No. 3.
Or take, for example, the strikingly and perhaps unexpectedly similar descending gestures, clearly identifiable as "blues" (4 -♭5 - 4 -♭3 - 1), that end local phrases in both John Coltrane’s “Mars” from Interstellar Space (1967) and Roy Harris’s Symphony No. 7 (1955) — at 1:26 and 6:33, respectively, of the recordings below. (Harris's figure continues with one extra tone, the lower ♭7.)
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