Playing music for baby

I've been playing music off of my cell phone for my little man lately and he goes absolutely nuts. I've been reading a lot online about whether or not its safe to set my phone on my belly while music is playing and there doesn't seem to be any real evidence to prove that it harms the baby in any way. Opinions? I've been just setting my phone near me and not on me. I'm more worried about how it affects his hearing, I don't want to play it too loud or anything.