Every sound you have ever heard was produced by contact. Two things met: a string and a finger, air and a reed, one surface and another. The Sanskrit term for such sound is ahata, struck. Against this the tradition sets anahata, unstruck, and defines it as sound not produced by any collision, which is a strange category by ordinary physics and a precise one within the system that uses it.
The claim is not that a very quiet noise exists somewhere. It is that vibration is the substance of manifestation rather than an event within it, and that what is prior to any two things meeting is therefore not silence in the sense of absence but sound in the sense of the underlying pulse. Struck sound is what happens when that pulse has already become a world with separate objects in it. Unstruck sound is that pulse before separation, which is why it cannot be recorded, shared, or pointed at.
The practice built on this is nada yoga, in which the ears are closed and attention is turned to what is heard internally. The texts describe a progression from gross to subtle, from sounds compared to thunder and drums down through bells and flutes to something likened to bees, with the instruction always to abandon the louder for the finer. The name of the heart chakra, anahata, comes from the same word, and the whole practice rests on the position set out under Shabda Brahman.
A sound that nothing makes is either nonsense or the most precise thing the tradition says, depending on what you think sound is. To see the metaphysics behind it, explore more of The Living Sanatan Timeline.
Part 19 of 100 — Series I: From the Beginning
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