Yoga, Tantric practices, and most forms of meditation share a purpose: to cease what Patanjali described in the Yoga Sutras as "the fluctuations of the mind-stuff," which has also been called "the chattering monkeys residing in our heads." And while it can sometimes seem a monumental task to still the mind, suitable only for monks or dedicated retreat-goers, there are many simple, effective meditative practices you can use to achieve tranquility. Exploring the interplay between sound and silence, both internal and external, can be a remarkable tool for entering into meditative states quickly and relatively easily, as a gentler and subtler approach than undertaking a silent retreat. Meditation has many well-documented benefits: inner peace, increased emotional resilience, and improved concentration, to name a few.

Many people are familiar with the power of sound in the context of mantra and chanting. The vibrational power of the chant is what makes it effective, in part. Try chanting "OM" for 10 or 15 minutes, and you will certainly experience the power of sound as a means to alter consciousness. At the same time, you are likely to discover that the really interesting states are experienced when the chanting stops and everything is still. Silence can be utilized to change consciousness and to quiet the mind. The contrast between sound and silence functions as a gateway into meditative states, and an emphasis on this contrast is typical of many forms of Tantric meditation. (And this interplay is what makes all music possible, though we seldom consider it from this perspective.)

The simplest meditation of this type actually occurs with every breath. The act of breathing produces a sound—a mantra that we are unconsciously repeating, constantly. The first step is to listen, and while breathing through the nose, pay attention to the underlying sound, which is often transcribed as "So-Ham" in Yoga and Tantra. This is the sound that initiates our existence and brings it to an end. Once you have become aware of the sound of your own breath, bring your awareness to the void between inhalation and exhalation, the point of silence when one is neither taking in air nor expelling it. While this may last only a microsecond, the process of becoming aware of this stillness can quiet the mind. Breathing should remain natural during this practice, since efforts to regulate it will disrupt the process.

There is another form of silent meditation that can be practiced while sitting near a busy city street or in any other environment. Antar Mouna, which means "inner silence," involves focusing one's hearing and ultimately turning that focus inward, thereby quieting the mind; external sounds themselves are the means to this end. Antar Mouna is a complex, multistage practice, but the first stage can be quite powerful in its own right; it requires you to focus your awareness on three specific aspects of your sense of hearing. The first is your experience of hearing itself, the second is the object that creates the sound, and the third is the "I" that is observing all of this. In virtually any setting, there exists an entire soundscape to explore in this way.

The process is quite simple. You might try it while sitting in a park. Close your eyes. Begin by allowing your awareness to rest on the most obvious external sound. Perhaps it is a bird. After a few minutes, move to a less obvious sound, perhaps children playing in the distance, then on to another, such as the rustling of leaves in a breeze. Continue this practice until you feel you have completely externalized your consciousness. Finally, turn your attention away from the sound, and concentrate on your inner experience; we describe this as withdrawing your consciousness into your head, like a turtle retreating into its shell. It is a kind of disconnection from the external stimuli, though you will probably remain aware of them at some level. Sit for a few minutes and simply observe what is stirring in your thoughts and feelings.

The classic Tantric text, the Vijnanabhairava Tantra, which is perhaps the best single guide to meditation ever written, describes another way of meditating on sound: "If one listens with undivided attention to the sound of string instruments and others which are played successively and are prolonged, then one becomes absorbed in the supreme ether of consciousness" (from Swami Lakshman Joo's commentary in Vijnana Bhairava: The Practice of Centering Awareness, Bettina Baumer, translator).