There's a Mysterious Low-Frequency Hum That Only 2% of People Can Hear — And Nobody Knows What Causes It

Imagine hearing a persistent, low-frequency droning sound that never goes away — a sound that most people around you can't hear at all. For about 2% of the population in certain areas worldwide, this isn't hypothetical. It's a real phenomenon known simply as "The Hum."

A Sound Without a Source

First documented in a 1973 British study, The Hum is described as a low throbbing background noise, typically peaking between 30 and 80 Hz — roughly the frequency of a distant diesel engine idling. It tends to be more noticeable during cool weather, often in the early morning, and can be confined to areas just 10 kilometers wide. What makes it truly strange is that each person who hears it perceives it at a slightly different frequency.

The Taos Hum

The most famous case emerged in the early 1990s in Taos, New Mexico, where residents began reporting a mysterious humming sound that seemed to come from everywhere and nowhere. A scientific study confirmed that about 2% of the local population could hear it, at frequencies modulated between 0.5 and 2 Hz. Despite extensive investigation, no source was ever identified. One resident reported the hum's range extended about 30 miles.

Around the World

The Hum isn't limited to New Mexico. Reports have surfaced in Bristol, England; Windsor, Ontario; Auckland, New Zealand; Kokomo, Indiana; and cities in Germany. In Windsor, a persistent droning vibration starting in 2011 was eventually linked to blast furnaces on Zug Island, a heavily industrialized area across the Detroit River. When the furnaces were shut down in April 2020, the noise vanished — one of the rare cases where a source was actually confirmed.

Still Unexplained

Despite decades of research, most instances of The Hum remain a mystery. Proposed explanations range from high-pressure gas pipelines to tinnitus to electromagnetic radiation. An audiologist at Addenbrooke's Hospital in Cambridge estimated that only about one-third of cases have a physical-world explanation, while the rest remain unexplained. For those who hear it, The Hum can be deeply distressing — it has been linked to at least three suicides in the United Kingdom. Whatever it is, The Hum continues to buzz at the edge of human perception, heard by a few, explained by no one.