A number of musicians are experimenting with brain entrainment and music. Brain Entrainment is any practice that aims to cause brainwave frequency to fall into step with a periodic stimulus. Steve Halpern has been experimenting with ancient sound healing traditions with quantum biology and energy medicine to produce recordings that support relaxation, stress management, yoga, meditation, massage, sleep, accelerated learning and pure listening pleasure. There is something about trying to achieve a binaural beat and brain entrainment.
The latter is the principle behind brain wave entrainment technologies.
Halpern has recorded music inside the Kings Chamber of the Great Pyramid...it's available by request.
He weds Tibetan and Egyptian music tradition and chanting along with modulating pitches at precise frequencies to achieve a very relaxing effect.
I put together a playlist on Youtube. It's great when you need to relax. Enjoy!