With all due respect I beg to differ from AJ Henderson's answer.
I don't think your parallel is off at all. Color and sound are a very good parallel in the context of trademarks and patents vs. copyright.
Actually there is a patent for the color "International Klein Blue (IKB)"
published in April 1961 after it was applied for by French artist Yves Klein.

MORE about this here:
http://en.wikipedia.org/wiki/International_Klein_Blue
and other color trademarks:
http://en.wikipedia.org/wiki/Colour_trademark
For sound, here are 8 sounds that have been trademarked:
The MGM Lion roar,
The NBC Chimes,
The 20th Century Fox Fanfare,
Harlem Globetrotter’s Theme (Sweet Georgia Brown),
Lucasfilms THX Deep Note,
Intel Inside Bong,
Federal Signal Q2B Siren,
AAMCO,
Unfortunately the Harley-Davidson attempt to trademark their unique exhaust sound filed in 1994 was later withdrawn in 2000 after years of litigation with competitors that appeared to have no end in sight.
More details here:
http://en.wikipedia.org/wiki/Sound_trademark