Free Music License?

[Alfred M. Szmidt]

   For me, one required freedom is to modify the whole document as I see
   fit. The GFDL currently fails to grant that freedom.

The GNU GPL also fails to grant that freedom, if by `whole' you
include the copyright notice(s).  Invariant sections are not
considered to be part of the main document; consider them as copyright
notices that programs print when you pass the `--version' flag.  The
main document may be modified as you see fit.