Here are a few truths we need to cognize about the science of sound :

Whatever that exists is Sound. The ancient Rishis (saints or mystics) discovered a long time ago that all of matter is sound, and sound is the original aspect of creation that acts as the substratum for everything else to come into existence. The original sound is ‘OM’. Upanishad (the sacred scripture of Vedic tradition) says Nada Brahman i.e. from the Nada(sound) the Existence expresses itself. The ancient Rishis discovered many expressions of Nada Brahman during the profound states of meditation. As the mind becomes quiet and subline, one hears subtle sounds corresponding to various chakras (energy centers) and levels of consciousness. All things were made by Him (the Word or Aum), and without Him was not anything made that was made.”
Nada holds the Form. Ancient Rishis were able to go deeper in their research of inner world. If we take the smallest molecule, we can find atoms inside the molecule, then going deeper down are the sub-atomic particles. Finally we land in the tiniest unit called quark. According to Vedic tradition, it is the Nada, the sound which acts as the energy field that binds the quarks together and retains the object as a solid form. So Nadais the ingredient which is responsible for the mud to remain as a mud pot. Whatever we see, the reason for things to remain in its shape, Nada is responsible for the forms or shapes!
Primordial Sound “OM”. The seed syllable “OM” or “AUM” is the most fundamental and potent mantra in the Vedic tradition. This mantra represents the underlying unity of Brahman or reality. Essentially, before existence and beyond existence is only One Reality, Brahman and the first manifestation of Brahman in existence is the vibration of “OM”. That is why “OM” is known as the pranava mantra, the source of all mantras. It represents both the unmanifest (nirguna) and manifest (saguna) aspects of God - meaning that it pervades all life forms and runs through our prana or breath. In the 1960s and ’70s, a Swiss engineer and medical doctor, Hans Jenny performed experiments using sound frequencies on various materials such as water, sand, dust, liquid plastic and milk. Dr Jenny placed the material on a metal plate attached to a crystal oscillator which was controlled by a frequency generator capable of producing a wide range of vibrations using the tonoscope. He then filmed and photographed what happened on the plate. He found a similar Sri Yantra after the “OM” chanting by a human voice. The ancient Rishis told us that the geometrical representation (yantra) of OM was the Sri Yantra which was proven by Dr Jenny’s research.

The 5 Elements. The human body is a microcosm (Pindanda) of the macrocosm of Universe (Brahmanda) because both are made of the same 5 elements (pancha bhutas) – earth, water, fire, air and ether. Ether is the subtlest form of all the elements which works on the space of consciousness. Only through use of sound vibrations that we can penetrate into the subtlest space. The sound vibration when it comes from the pure source, uncreated it is called Anahanta Dhvani i.e. the sound which is created not by 2 things striking each other. When theAnahanta Dhvani gets mixed with the sub-atomic particles, it retains the quarks in different forms through its energy binding force that is responsible for solid existing. Everyone of us has the ability to listen to this sound if we are able to tune ourselves to it.
Diseases and Sound are Related. Sound energy field is responsible for the diseases we carry. If our energy field is altered, naturally our diseases will be cured. Therefore, Nada is responsible for our health or diseases. All authentic healing systems in the world work on Nada, i.e. all healing happen on energy of Nada.
Healing Power of Mantras. The word “Mantra” means “to free or protect”, referring to freeing one from the bondage of “samsara”, our habitual tendencies. In another words, mantra means sound that which protects those who reflect on it or which helps to cross the mind to consciousness. Many of us are bound by habitual tendencies but when the mantra is substituted for these tendencies, one becomes liberated from them. Repetition of certain mantra removes those desires which obscure one’s vision such as anger, fear, greed and lust. Mantras have the cleansing effect to help our mind reflect the reality of higher spiritual truths. Mantrachanting bestows peace, bliss, illumination and consciousness. It can awaken the intellect by opening the intuition which, in turn, inspires the intellect. Creative thinking starts happening spontaneously and inspiration dawns within one’s inner space.
Bija (seed) mantras. All mantras are oriented towards different aspects of the Divinity. The most powerful mantras contain the bija syllables or sounds which were discovered by Siddhas (Vedic saints) as the keys to higher states of consciousness. These bija mantras have no meaning by itself but the vibration in the human-mind system is very powerful in awakening higher consciousness. The 6 bija mantras are – om hram, om hrim, om hroom, om hraim, om hraum, om hraha. They contain a transformative divine power (shakti) which manifests through sound. Each bija mantra has a corresponding pattern (yantra), a geometric, mandala-like form.
Language of Divinity. In the world, there are 2 kinds of languages: 1) those which are used to communicate between common men such as English, French, Mandarin, Hindi etc. and 2) those which are used to communicate between the different levels of consciousness. Most people are only interested in the common man language as the second kind exists only in many spiritual or religious traditions. Nada Brahman and mantras belong to the language of conscious cognisance i.e. deva bhasha. Learning of mantras should happen in a spiritual community where both the students and the atmosphere have been purified by the various yogic practices, and only from the teachers who have experienced the mantras and its states of consciousness.