I’ve had some experience with this for meditation: https://www.youtube.com/watch?v=QJImZyWqMWs
The problem with synthetic music is that you never know what kinds of subliminal messages and God-Knows-What they’re putting into it. For meditation I prefer gregorian chants, and even though my experience is somewhat limited (still!), it would appear that shamanic drums are most effective for would travel (Thanks to Lady Eva for pointing that out!).