(let* ((m (make-music 'PartCombineMusic))
(m1 (make-non-relative-music (context-spec-music (first music-list) 'Voice "one")))
(m2 (make-non-relative-music (context-spec-music (second music-list) 'Voice "two")))
(let* ((m (make-music 'PartCombineMusic))
(m1 (make-non-relative-music (context-spec-music (first music-list) 'Voice "one")))
(m2 (make-non-relative-music (context-spec-music (second music-list) 'Voice "two")))