Can you hear it?

Imagine you woke up one morning and heard a noise — a low rumbling hum, similar to a truck running outside your house. You never noticed it start; instead, it gradually crept into your consciousness until you were suddenly aware of its presence. This sound is known as the Hum and it has plagued less than 2% of the worldwide population for years. But what is the Hum and where did it come from?

The first reports of the Hum began in Bristol, England in the late 1970’s. After a local newspaper published an article in 1977 called, “Have You Heard the Hum?” hundreds of Bristol residents reached out to confirm that yes, they had.

Over the last forty years, humans have reported hearing the Hum from across all corners of the globe. Those who can hear the Hum say the sound doesn’t appear to come from any one direction, making it impossible to pin down the source of the noise.

Some experts attribute the Hum to tinnitus, an auditory symptom that affects one in every five people. However, tinnitus has been around for as long as humans have, yet the Hum only started gaining attention in the late 20th century.

Other experts believe the low frequency noise might be caused by an external source — perhaps something technological. But as sound spreads, it diffuses and becomes softer, so it’s unlikely that the same outside noise would affect so many different people across so many locations.

Then there’s the fact that people experience the Hum differently. Some describe the sensation as a vibration in their inner ears. Others are only able to hear the Hum when they’re sick or feeling stressed. Some hear the Hum every day in specific locations.

Those who hear the Hum believe that the noise originates from an external source. One Bristol resident who has heard the Hum for years experimented with noise canceling headphones and found the sound would disappear completely when he had them on. Another Bristol resident who travels frequently for work has only heard the Hum inside his own house.

Those who hear the Hum say that the worst part of the experience is the uncertainty; that not knowing what the noise is or where it comes from makes them that much more aware of its presence. Those afflicted complain that the Hum keeps them awake or prevents them from completing their work. The noise is so pervasive and maddening that it has led to the suicides of at least three people.

We may never find what the Hum is or what causes it. Those who hear it may never find relief from the sound. But as it stands right now, the Hum is one of the world’s coolest and most interesting unsolved mysteries.