Laya yoga is the absorption of the mind in sound. The goal of this practice is to alter one's normal awareness of self by focusing on hearing an internal, mystic sound. The mind will become steady and absorbed in the sound on which it focuses. In space, sound is produced by the movement of sound waves in the air. So, too, in the body, there are currents that flow and produce sound when one practices pranayama.
To do this practice, sit in siddhasana and focus the attention on the spot between the eyebrows. Turn the eyes upward and let the lids remain closed. The eyes, ears, nose, and mouth should be closed. With a calm and controlled mind listen for a sound in the right ear, and eventually you will hear a clear sound. In the beginning the sounds will be very loud and varied, but with continued practice they will become increasingly subtle. At first one may hear sounds that seem to pound and surge, like the beating of a kettledrum. After some time, in the intermediate stage, the sounds will resemble those produced by a conch shell, or by bells. Finally, after further practice, the sounds will resemble tinkling noises, the sound of a flute, or the hum of bees. All of these sounds are produced within and cannot be heard by anyone else. One should practice being aware of both the loud and subtle sounds, alternating and varying one's awareness from one to the other, so that the mind will not be inclined to wander.
When the student's mind is intently engaged in listening to these sounds, he becomes captivated by them and overcomes all distractions. As a result of this practice, the mind gives up its outwardly directed activity and becomes calm, desiring no objects of sense gratification. The mind and breath become refined and one's attention is focused within. Then the yogi forgets all external objects and loses consciousness of himself, and the mind is absorbed in bliss. The absorption that is produced when the mind enters the sound (nada) emanates spiritual powers and a sort of ecstasy, and one forgets his whole material existence. If one desires to attain this state of union, one should practice listening to the anahata sound in the heart with a calm and concentrated mind. When the mind focuses on the sound, it becomes steady. Mental activity is suspended when the mind is absorbed in the sound. The accomplished aspirant interpenetrates the anahata sound and attains the state of samadhi through this method, laya yoga.
These internal sounds can be heard only by those whose nadis are free from impurities and who are well practiced in pranayama. The anahata sound comes from sushumna, and, as with other sounds, it cannot be heard by the aspirant until this nadi is free from all impurities. Thus the practice of concentration and absorption with nada (sound) is only possible after considerable preparation. A beginner can instead perform bhramari kumbhaka, in which a humming sound resembling a bee drone is produced in one's throat. This practice requires breath control, so that the breath may be exhaled very slowly, producing the sound for a significant length of time.
Just as focusing the awareness on the eyes produces special powers of vision, directing one's awareness to the ears allows one to detect special sounds. By directing the full force of one's attention to these senses, the deeper powers develop. Directing the thoughts to any particular sense of the body awakens one's conscious awareness of the powers that correspond to that sense. Concentration upon the organs of the body that are involved in any practice increases their power and sensitivity, and intensifies and strengthens that organ system.
Concentration shows itself in five progressive mental stages: analysis, reflection, bliss, ecstasy, and meditation. The first stage is one of gaining knowledge about the nature of the object. The second step is that of pure reflection; here the lower stage of analysis is transcended. In the third stage, the power of reflection gives way to a blissful state of consciousness, which later merges into the pure ecstasy of the fourth stage. In the fifth stage, one losses awareness of all sensation and external awareness gives way to a state of complete meditation. In samadhi, there is neither seeing nor hearing, neither physical nor mental consciousness; pure existence and total absorption on the absolute is experienced.