With more than half the world’s population now living in towns and cities, more and more people are searching for silence. Noise pollution is continually in the headlines, and an industry has sprung up for those seeking peace and quiet, selling everything from noise-cancelling headphones to silent retreats.

Writers too have jumped on the bandwagon. Recent bestsellers have included the Buddhist monk Thich Nhat Hanh’s 2016 Silence: The Power of Quiet in a World Full of Noise, and the Norwegian explorer Erling Kagge’s 2017 In Search of Silence in a World of Noise.

I’m not sure, however, that there is much point in searching for silence. Forests buzz with the hum of insects, barren mountainsides amplify the smallest sounds, and deserted beaches never lack the roar of ocean waves. Perhaps there is no such thing as silence.

That is what the experimental composer John Cage often argued.

Cage claimed to have come to that realization during his 1951 visit to the anechoic chamber at Harvard University. Constructed at the behest of the US army air forces during the second world war, the chamber’s designers originally used it to find ways of combating the fatigue inflicted on bomber pilots by the immense noise of the piston engines then in use. Insulated against external noise by thick concrete on the outside, and lined on the inside with 20,000 fibreglass wedges to suppress echoes, the Harvard chamber was supposed to be one of the quietest places on Earth. Yet Cage claimed that he could still hear two distinct sounds, one high and one low, asserting that the former came from his nervous system and the latter from the circulation of his blood.

I have found Cage’s story about the anechoic chamber fascinating ever since reading it as a teenager. I am not the only one: many have sought to replicate the experience. Some have cast doubt on Cage’s claims about what he could hear, while others have suggested that the encounter with complete silence drove them mad – even to the point of hallucinating.

I decided to find out for myself. I scored a tour of the anechoic chamber at the Cooper Union, New York’s premier university devoted to science and the arts. Situated in the vibration and acoustics laboratory, the anechoic chamber is the only one of its kind in the city.

My partner and I were kindly shown around by Dr Martin Lawless, who researches the brain’s emotional responses to concert hall acoustics. Albeit far smaller than its now demolished predecessor at Harvard, the anechoic chamber at Cooper Union also depends on fibreglass wedges for its effect.

Surrounding you on all sides, down to the ground beneath the metal grate you stand on, those wedges are individually positioned to prevent soundwaves from travelling back towards their source. In addition, the chamber is so thoroughly insulated against external noise – as well as having thick walls, it is suspended in a void of air – that those on the inside would never stand a chance of even hearing the fire alarm go off.

We couldn’t resist testing the soundproofing by taking turns to step outside and emit piercing screams. Nothing was audible.

Once we settled in, my experience soon began to confirm Cage’s assertion that silence was not really the chamber’s defining quality. Like him, I quickly became aware of noises that I wouldn’t normally have been able to notice – a hint of tinnitus in my ears, and the rustle of my partner’s breath.

For Cage, the revelation that silence was impossible served as the linchpin for an entire musical aesthetic. In perhaps his most famous composition, the performers simply sit in silence for 4 minutes and 33 seconds. Much derided by conservative music critics, 4’33” is an acute comment on the relatively recent convention of listening to “art” music in reverential silence. Encouraging audiences to focus on that silence rather than the music for which it is reserved, the piece enables you to find a new symphony of beautiful sounds, whether traffic from outside the concert hall, or the coughs of your fellow concert-goers.

But I began to suspect that Cage had missed the most important thing about the anechoic chamber. He had focused more on what he failed to find – silence – than on what was actually there: the remarkable transformation sounds undergo when there is no echo. The familiar clink of metal on metal, for instance, came out as a dull thud, almost like the muffled sound of wood hitting a piece of felt. The clapping of hands was equally lacklustre.

The experience was like being transported into a surrealist film, with new sounds dubbed over the ones we would normally expect to hear. The result was not particularly frightening – nothing like the far-fetched tales of panic attacks and hallucinations I had been reading about. But it was strange, and decidedly lonely.

My time in the anechoic chamber was a forceful reminder that most of the sounds we hear come to us indirectly; reflected into our ears by the things and people around us. Sound is a shared experience, formed as much by the environment we live in as it is by whatever happens to produce it in the first place. The anechoic chamber shows us what it would be like to live in a world that gives nothing back: a lonely world where sounds simply evaporate without returning.

Minutes after coming out of the room, I found myself back on Cooper Square, in Lower Manhattan, immersed again in the sounds of the city. But I didn’t mind them as much as I had before. Hearing the roar of a truck barrelling down the Bowery, I listened out for the reverberations handed back to me by the buildings on either side of the road.

On a side street, a more delicate scene unfolded. I noticed the quiet chirp of birds reflected by the hard surfaces of the flagstones and brownstone houses. Cage was right to point out that the search for silence is impossible. But the anechoic chamber teaches us how to enjoy the echoes that endlessly reshape our perceptions of the urban landscape.