The Last Word On Nothing

Manhattan rattles my ears. Subway lines shake the fine bones inside my head. Cars honking on the street change the way my brain physically functions. When I stayed in the city a week ago I noticed the same as I always do: noise.

I live in a quiet place off the grid in Western Colorado and when I plunge into urban melee it is a primarily aural experience. Much of the city runs at about 85 decibels, a level that takes just eight continuous hours to permanently kink the hairs transmitting sound through the inner ear. The average subway ride comes to around 112 dB, somewhere between a shouted conversation and a power saw going off near your head.

An audiology researcher in Berkeley, California, informally tested the sound of his local transit system and found sustained peaks at the level of a rock concert (around 120 dB). On top of that, he noted, many passengers were wearing ear buds, listening to music loud enough to mask the external noise, far exceeding limits on volume and time-exposure that lead to permanent damage and hearing loss.

I’ve made a habit of seeking out the quieter places in the city, this time taking shelter in a poetry reading room. At other times I’ve gone to Wall Street at dawn on a Sunday morning for its towering quiet or, once, the Ramble in Central Park at night, also quiet but disturbingly dangerous.

Every city has its sanctuaries from noise. The most profound I ever encountered was an anechoic chamber in a basement on campus at the University of California, Berkeley. This soundless chamber sits on the bottom floor of the Hafter Hearing Center, overseen by retired audiologist Erv Hafter, who took me inside. Hafter carefully explained that an anechoic chamber is not an infinitely silent place. As far as he knows no such thing exists on Earth. He said there are movements in the ground, vibrations, jackhammers, even distant earthquakes.

As we stood in the master bedroom-sized chamber, I asked if I should be able to hear anything, and he said no.

“Sound may enter your ears, but you’re not hearing it,” Hafter said.

“It’s not reaching the brain?” I asked.

“Yes, it reaches the brain, but the brain is a filter. One of perception’s most important functions is to forget.”

In other words, silence, like noise, is what your brain allows you to consciously experience. The rest you decode and dismiss.

Covered top to bottom and side to side with foam-core filters, the space absorbed all noise but what was aimed directly at me, in this case Hafter’s voice. I could not stop staring at his mouth as he talked. It was as if he were speaking down a tube. I could hear his spit. Between words came a brief and eerie deadness, the room absorbing every sound. There was not a single detectable reverberation.

Hafter went to the large airlock door. “I’ll just shut you in. Take as much time as you need.” He drew closed the door, and I stood in silence, listening for earthquakes in China.

Used for sound experiments, the chamber is lined with speakers and trunks of electrical cables. The floor is a springy net of wire suspended over geometric baffles. The wires strained, sounding like violin strings under my feet as I slowly paced the room’s perimeter. I could not hear where I was, my ears fighting with my other senses. My eyes said I was in a closed space, but my ears said I was floating in an infinite void. Usually a person hears an entire auditory environment by detecting waves bouncing this way and that. In the chamber there was no context; it’s a sensory black hole.

An audiologist doing sound research with babies once told me anechoic chambers always made them cry. He said, “You have a perfectly quiet, normal 10-month-old, happy as a lark, maybe even half asleep; you bring them into an anechoic chamber, and they go berserk.”

I pulled the chains on four light bulbs, plunging the room into total darkness. It felt as if my senses were suddenly cut off, a sensation that would have driven a 10-month-old stark raving mad. We need sound as much as we need silence, maybe even more.

With vision removed from the equation, I focused on what I could hear, which at first was nothing. Muscle tension eased off my tympanic membrane, and the tiny bones in my ears relaxed, their tendons letting the hammer down. I began to hear the soft thrum of my heart. Then came a fainter noise, a hiss. It was not as sharp as the ringing in the ears known as tinnitus (the result of damaged hearing where auditory neurons fire off randomly because they are not being stimulated). I thought it was an air duct, but no air comes or goes from an anechoic chamber. I tilted my head one way and the other, trying to fix on the sound’s singular location, and realized it was in my head. It was, I believe, the sound of blood flow echoing through my skull, like sand pouring across velvet.

I lasted 45 minutes, then pulled the chain on each light, popped open the heavy door and emerged. I took an elevator up, pushed through the outside doors and stepped onto campus as if coming up for air. It was like getting my senses back, the relief of jet-noise and thousands of bustling students.

Last week in Manhattan, I found no anechoic chamber. I drifted through rivers of noise. The quietest it got on the street was a steady rain one night. Rain comes in around 50 dB. I could appreciate this sound because it wasn’t the human cacophony. Rain on sidewalks and the bluster of wind between buildings masked the maddening noise going on the rest of the time. At least then I could shut my eyes under this hiss on my umbrella and relax.

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