A collection of classical tracks recorded by Kevin MacLeod under the Creative Commons Attribution license. Famous pieces, including Richard Strauss' Also Sprach Zarathustra, and Tchaikovsky's Dance of the Sugar Plum Fairy, settle in nicely among Kevin Macleod's own compositions. Found at http://incompetech.com.

https://freemusicarchive.org/music/Kevin_MacLeod/Classical_Sampler