In this article, Swami Satchidananda explains the science behind the relationship between sound vibrations and prana (subtle energy). He teaches the practice of ajapa-japa—concentration upon the natural sound of the  breath which continually repeats the mantras Soham and Hamsa.

Prana is a subtler vibration than sound vibrations. We only hear certain octaves of a sound. There are 20,000 vibrations per second. Over and below, it is not heard and is not called sound. What we hear as sound is only part of the vibrations. But prana is the cause of all the vibrations. It is prana that makes everything vibrate. In a sense, it is prana that takes over the various forms, to vibrate in different levels. It’s not that prana is something different and it makes something else to vibrate. Prana is the basis of everything. You can say that prana is omnipresent, omniscient, omnipotent.

The Vedas, ancient Hindu scriptures, talk about different sounds. They say that sound begins at the navel and then comes up to the throat and then comes out. You don’t hear much at the navel or the throat but you may be able to hear a little, if you block the outside sound, go within, and listen carefully. That practice is part of Nada Yoga which means contemplating or listening to the inner sound. We do have that inner sound which is not audible to everyone. And that is what you call the hum or OM. Anagata is another name for that. It means, unheard sound. Can you think of a sound that’s unheard? You’ve never heard of it. So the relationship between sound and prana, is that sound, is the expression of prana. And prana is subtler than the sound itself. Sound vibrations can reveal to you the basis of the sound, which is prana. We cannot directly go and do anything with prana. So we begin from a grosser level. We work with the body first, through Hatha Yoga. And then, slowly, from the concrete we go to the subtler level, to the prana. We practice some pranayama, and then from the prana we go to the senses and from the senses we go directly to the mind.

Our aim is to understand the subtle. But, because we are in the physical level, we have to go from the physical level to the subtle. That’s why physical sound can lead us to the inner sound and the inner vibration—the prana. That’s the reason we have chanting and mantra repetition. The inner sound is constant. Actually, it’s the inner sound that makes the breath move. If you listen carefully, you can hear the breath itself creating certain sounds. That’s where the mantras Soham and Hamsa come in. It goes in as soooo ham. It is always repeating within. Ajapa japa means sound. Japa without japa. You just sit quietly and listen to the breath. The breath repeats the mantra, soham or hamsa. It’s the same mantra, forward and backward, and of course, there is an external meaning also. Hamsa is a swan. The Vedantic term is Soham: I am that I am, which is an expression of that. It’s expressed in various ways. But the breath always repeats that sound.

The Practice

Relax your body. Sit comfortably so that you will not  have to move for a while. Try to keep your spine erect, chest a little spread out, and feel the weight of your body right on your seat. Find the center of gravity and  just be relaxed. Close your eyes. Concentrate on your  breath and begin to breathe deeply; exhale fully and inhale deeply a few times. Have slow and deep exhalations and inhalations. Let the mind follow the breath; forget the entire outside world and let the total awareness be on your breath now. Slowly, we are going to go into the very source of the individual personality. Do not put any effort into your breathing but just allow the breath to flow normally. The breath may become very shallow but continue to follow it.

Listen to your breath. If you Iisten carefully, you  will be able to hear the sound “Soham” [“a” is pronounced as the “u” in up). So when the breath flows in, Ham when the breath flows out. It may be difficult in the beginning to hear it, but as the attention gets drawn inward you will hear the breath repeating it. You need not repeat it yourself—just listen to that and you will be able to hear that sound. After practicing this for some time, you may begin to hear a humming musical note within you. Constantly listen to this hum. This is part of the cosmic vibration. By concentrating on this inner vibration, you are in tune with the cosmic sound.

That is why you are able to feel peace and bliss. Let there be a complete void except for this musical note. By remaining in this state, you are sending out powerful peace vibrations that travel all over the globe and influence other minds, even restless minds. In this very high state of silence we have forgotten all our differences; we feel that we are One, you will be feeling very light; you will have transcended your body, and you will feel that you have expanded and lost your individuality temporarily to be one with the cosmic mind.

After sitting for some time in silence, slowly direct your attention toward your breathing and gently make the breath a little deeper. Continue to deepen the breath for a few minutes and then close the meditation with a chant.

Chant:

Asatho Maa Sat Gamaya

Thamaso Maa Jyothir Gamaya

Mrithyor Maa Amrutham Gamaya

Lead us from unreal to Real

Lead us from darkness to Light

Lead us from death to Immortality

Om Shanti, Shanti, Shanti

Om Peace, Peace, peace

Lokaa Samastaa Sukino Bhavanthu

May the entire world be filled with peace and joy.

Source: Excerpted from the booklet, Meditation by Sri Swami Satchidananda