My main thing is that the music shouldn’t be all that interesting, but beutiful
Michael Hoppe - Wing Songs (interesting but relaxing, and so old I’ve trained myself to autorespond to this)
Brainsync - Inner Mind dep meditations
Best for me:
Plain Shamanic journey drumming (no music, it’s just drums to keep the frequency and refocuses me without being distracting. There’s three tracks on this, a calling, a drumming track of 1hr and a callback track but I have the main track on loop and do my own open and close.)
The trouble I have with music is that it gets in the way - it influences my mood but also makes it hard to hear etheric music and voices if I can still hear it when travelling. (Your body can have music stored in it also). On top of that you can connect to the musician through the music and start picking up their story, which can be confusing. I like a free working area.