I used to use this quite a bit and create my own experiences. What is does is force your brain waves into different states of consciousness (usually theta, associated with sleep). It takes a while to learn and get your brain used to making changes while conscious. After a while though it is possible to do without the listening to the "beats".
It's not really music, but it’s like these two tones, one in each ear that produces the beat, which only exists in your head. So you sit there and listen to two tones, then you start to hear a beat, but is more sounds like ocean waves. Then it becomes almost like you feel like dreaming and if you close your eyes you might start to.
With enough training one can begin to lucid dream and it's hard to explain but in some of the sessions I experienced what could only be explained as a non-sexual full body orgasm of pure bliss. It also reduces the amount of sleep one would require in order to feel properly rested. It is really good stuff and even better when you learn to shift your brain waves without the beats while conscious.