The Sound of Noise & Silence

Among many things we will remember after the coronavirus pandemic, the world was quieter than normal. When I compared a busy avenue-street intersection in Manhattan before and during the lockdown, I found a 6 decibel (dB) difference, four-fold in amplitude. (The vast range of sound detected by the human ear needs the logarithmic scale.) A lower density of traffic on the ground, underground and overhead was mostly responsible, with contributions from building work, human voices, and so on. In suburbia, it is weed whackers, chainsaws, and trucks that make most of the racket, and sometimes neighbors too! You can check out a noise map for your region and community here.

Human ear and listeningI can’t think of any virtues for noise, though we don’t agree on the main offenders. Objections are sometimes muted by vested interests. Noise is in the ear of the beholder. Sounds that some heads perceive as musical turn others in disdain or even pain. I remember marveling at the virtuosity of nightingales singing through the night in Languedoc. The volume can reach 95 dB, above the threshold of harm for human hearing.

… That thou, light-winged Dryad of the trees

In some melodious plot

Of beechen green, and shadows numberless,

Singest of summer in full-throated ease …

John Keats: Ode to a Nightingale

Music is mostly regarded as the antithesis of noise, but commonly causes hearing loss. Rock music at concerts and through headphones, for instance, but players of classical music are also at risk, especially French horn players, and when did you see them wearing ear protection? A trombone and trumpet can even register around 110 dB.

The world gets ever noisier, affecting mental well-being and wildlife. The background soundscape can swamp bird song and amphibian calls needed for wooing mates and defending territories, and sound from shipping and industry is conducted faster and farther through water, harming marine life. Even national parks can be noisy. I registered 65 dB at a car park in Yellowstone and had to hike far from human activity to find a nadir of 30 dB, equivalent to a soft whisper from signing leaves and boughs in still air.

We may seek quiet places for peace, but, please, not too quiet. Plunging below 30 dB is strange and uncomfortable, though few people experience it. When I sat in an anechoic chamber in a lab the ringing in my ears was unpleasant, like so much static (tinnitus). Exploring a labyrinthine cave was probably as silent as outer space, but I never noticed discomfort one day deep underground because I was lost and focused on finding a way out! Just as our brains can blot out noise, they can filter out silence too.

While noise irritates, silence is fascinating, even when it makes us feel uncomfortable. When John Cage’s enigmatic 4’33” composition was performed in 1952, the audience heard the soloist close the piano keyboard for the 3 movements. That’s all, except it wasn’t strict silence—someone coughed and there was a ripple as another suppressed a giggle. Some people interviewed afterwards said they felt insulted or cheated, whereas others said it made them watch and listen more intently than usual. I never heard this composition live, although I often listen in solitude or helped by watching dogs teach alertness to everything around, even when they seem to be dozing. May a quieter planet continue to reign after the pandemic.