Posted 06 September 2013 - 09:19 AM
Johann Strauss (aka "The Waltz King") died in 1899, so you're ok. (not to be confused with Richard Strauss, also a famous composer who died in 1949)
Not all "classical" compositions are in the public domain yet, as Hans Zimmer discovered after he was sued by relatives of the late Gustav Holst. Music from Gladiator (which ZImmer did the score for) sounded remarkably like "Mars" from "the Planets".
Always check both the current law, date of composition and date of death of the composer whenever you want to use a musical work.
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Music Composition & Sound Design
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