You definitely want to use both components together. They are equally important. While the "music" tracks actually change your brainwave frequency, the disc disables your stress response to make sure it doesn't override what the music is trying to do and the eyemask is important for eliminating visual stimuli that can prevent certain brainwave frequencies from occurring.
Could one theoretically also get a benefit out of the soundtrack alone or is it mandatory to always use it in conjunction with the discs or it will otherwise not be effective?
