While this story from Wired about music for monkeys might be a few months old, it's still a fascinating read. Entitled "Monkeys Don't Go For Music -- Unless It's Made for Them," it demonstrates that monkeys don't really respond to human music, instead preferring silence.
However, "when a psychologist and a musician collaborated to compose music based on the pitch, tone and tempo of tamarin calls, they discovered that the species-specific music significantly affected monkey behavior and emotional response."
When you read the whole story, they have two monkey "songs," 30-second pieces made with human voice and cello, "based on specific features from recordings of tamarin monkey calls." The recordings are actually far more tuneful than your average experimental music piece, but are probably no more appealing to humans than blasting Melt Banana at a gibbon would be.
Of course, in news that should be of no surprise to anyone with pets, David Teie (the composer who collaborated with psychologist Charles Snowdon on the paper) has started a company called Teyus, which is "the world's only provider of species-specific music to institutions: authentic cat music based on feline communication and hearing."
That music is far more pleasant to listen to than the monkey music, and my cats will probably enjoy it more than the Japanese hardcore I was blasting a couple days ago. Still not as good as this, however: