While we are at it, the following is a selection of musicians whose work for me is both sedative and promotes focus (an oxymoron?). Ambient music usually garners a few sniggers, "this is what they play in spas" "whale music" etc, however in my experience can be an incredibly rewarding and effective method of relaxation and enjoyment.

Gas (Wolfgang Voigt) - Pop https://www.youtube.com/watch?v=s--IkNqI9og

Brian Eno - Discreet Music https://www.youtube.com/watch?v=SE6nQ0lkLdY

Willits + Sakamoto - Reticent Reminiscence https://www.youtube.com/watch?v=vdJdDwi1RS4&list=RDdskvPFt7w...

Aphex Twin - Stone in Focus https://www.youtube.com/watch?v=IG16BTj5qT4

Bvdub - A Moment's Peace https://www.youtube.com/watch?v=exr3IAMaLPM

cv313 - Beyond The Clouds https://www.youtube.com/watch?v=pqrRIDd5pSk

If you enjoy this type of music I thoroughly recommend the Headphone Commute blog. Apologies if a bit off topic.