NaDa

Nāda yoga (नादयोग) is an ancient Indian metaphysical system. It is equally a philosophical system, a medicine, and a form of yoga. The system's theoretical and practical aspects are based on the premise that the entire cosmos and all that exists in the cosmos, including human beings, consists of sound vibrations, called nāda. This concept holds that it is the sound energy in motion rather than of matter and particles which form the building blocks of the cosmos.

Nāda yoga is also a reverential way to approach and respond to sound. In this context, sound [and] music carry a spiritual weight more meaningful, respectively, than what sensory properties normally provide. Sound and music are considered to play a potential medium/intermediary role to achieve a deeper unity with both the outer and inner cosmos.

Nāda yoga's use of sound vibrations and resonances are also used to pursue palliative effects on various problematic psychological and spiritual conditions. It is also employed to raise the level of awareness of the postulated energy centers called chakra.

Music has been used by most Indian saints, prophets as an important and powerful tool in the quest for the achievement of nirvana; notable names to be mentioned here include Kanakadasa, Thyagaraja, Kabir, Meerabai, Namdeo, Purandaradasa and Tukaram.

The Nāda yoga system divides music into two categories: internal music, anahata, and external music, ahata. While the external music is conveyed to consciousness via sensory organs in the form of the ears, in which mechanical energy is converted to electrochemical energy and then transformed in the brain to sensations of sound, it is the anahata chakra, which is considered responsible for the reception of the internal music, but not in the way of a normal sensory organ.

The anahata concept refers to one's own personal sound vibrations, which are thought to be so closely associated with one's self and the Self that a person can not share their anahata with another human being. In other words, this inner sound is sacred and once reached will open the practitioner's chakras, which ultimately will unite the body to the divine/cosmos.

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Wikipedia