This double CD set--recorded “live” in Japan in 1975 and, until now, only released there--amounts to the trumpeter’s swan song before his six-year retirement in the late ‘70s. Dense and intensely electric, “Pangea” has an urgency driven by double guitars and percussion. The takes are long, and match head-on, devil-may care modal charges with mournful dirges that build to roaring, affirmative climaxes. Sonny Fortune’s winsome flute, drummer Al Foster’s shimmering, open hi-hat sound and Michael Henderson’s pendulous bass contrast with the weary-sounding trumpeter’s cries and whimpers, which are further smeared by electric wah-wah effects. This is a striking personal soundtrack of decline that, like Miles himself, suffers from exhaustion before playing itself out.