Healing Delight- Color/Sound Therapy

I always believe that sound is the most powerful therapy of mental illness. People use sound to relax and meditate as well. For example, when we do yoga, we will listen to some kind of relaxing music as we gesturing. Referring to religions, Hindus also listen to some kind of vibrated, rounded echos when they are doing meditation. 
I found this one of the sound therapy videos in youtube.