John Fahey’s reputation rests on his’60s recordings, elaborate explorations of acoustic folk/blues that erased distinctions between roots music and the avant garde. By the ’90s, however, Fahey had become disgruntled with his legacy. He switched to electric guitar, dabbled in industrial murk and seemed studiously indelicate. Red Cross, finished just before his death in 2001, marks a surprising reconciliation with his old style. Fahey’s playing remains hesitant, but for contemplative rather than alienating ends, as he turns uptown standards by Irving Berlin and the Gershwins into spectral, rustic laments. A bewitching last testament.