Leonard Burkat, who wrote the house notes for, among others, the National
Arts Centre Orchestra, always stressed in his notes for a work by Handel or
Bach [and I paraphrase} That there was finally a "new" piece of music worth
saving, rather than "old" music, worthy of being forgotten.

This suggests the there was 16th or 17th century equivalents of'heavy
metal' which had a limited life span.

Take Elvis Pressley and Hound Dog..  We all remember it because it was
written in modern times; but will it be remembered and played in the 23rd
or 24th century, whereas the music of Aaron Copland and Benjamin Britten
will.

Perhaps durability is principal of classical music.

Sincerely,

Alex Renwick,
Ottawa, Canada