The Taos Hum is a persistent, low-frequency sound heard by a small percentage of people in and around Taos, New Mexico, that has no confirmed source. First widely reported in the early 1990s, the sound falls between 32 and 80 Hz, roughly the range of a deep bass note or a rumbling engine. Despite formal investigation, no one has been able to definitively explain where it comes from or why only some people hear it.
What the Hum Sounds Like
People who hear the Taos Hum don’t all describe the same thing, and they don’t all hear the same pitch. When researchers tested hearers in Taos, individual frequency matches ranged from 30 Hz to 80 Hz, with a slow pulsing rhythm (a modulation of 0.5 to 2 Hz). Even two people standing right next to each other would identify different frequencies as their match. This isn’t one uniform tone. It’s a deeply personal experience that varies from hearer to hearer.
The most common description, given by about 65% of hearers, is the sound of a diesel truck idling in the distance. Another 27% compare it to a transformer humming, 14% say it sounds like a droning propeller plane, and 11% liken it to the chugging of a fishing boat. These categories overlap because people were allowed to choose more than one description, but the common thread is always the same: a low, droning, mechanical sound that seems to come from everywhere and nowhere.
How It Differs From Tinnitus
Tinnitus, the ringing or buzzing that millions of people experience, is generated entirely within the ear or auditory system. The Taos Hum shares some surface similarities, but researchers have identified key differences. Standard tinnitus typically involves higher-pitched sounds, often a ringing or hissing. The Hum sits at extremely low frequencies, well below what most tinnitus patients report.
One line of research points to a specific mechanism in the inner ear. The vestibule (the part of the inner ear responsible for balance) and the base of the cochlea (the part that processes sound) may create a kind of resonant feedback loop. In this model, electrical signals from the vestibule, sound pressure at the cochlear base, and external sounds interact to produce a phantom low-frequency tone. This would make the Hum a distinct form of extremely low-frequency tinnitus with a different origin point than the conventional kind. It also helps explain why only certain people are susceptible: minor anatomical differences in the inner ear could make some individuals more prone to this resonance.
The 1993 Investigation
By the early 1990s, enough Taos residents had complained about the sound that the U.S. Congress asked researchers to look into it. A team from the University of New Mexico and other institutions conducted a formal study and found that at least 2% of the local population could hear the Hum. That might sound small, but in a town the size of Taos it meant dozens of people were affected.
The researchers confirmed the frequency range of 32 to 80 Hz and documented the slow pulsing quality of the sound. What they couldn’t do was record it. Sensitive microphones and acoustic equipment failed to pick up a matching signal in the environment. The investigation ended without a definitive answer, which only deepened the mystery and public fascination.
Leading Theories
Very Low Frequency Radio Waves
One of the most discussed hypotheses involves VLF (Very Low Frequency) radio transmissions operating between 3 kHz and 30 kHz. Military forces around the world use massive ground-based and airborne transmitters at these frequencies to communicate with submarines, because VLF waves can travel enormous distances and penetrate deep into water and even through solid materials. Geophysicist David Deming was among the first to propose that these transmissions could be responsible.
The idea rests on growing evidence that the human body can sometimes convert electromagnetic energy into perceived sound. Biophysical models now exist that describe how VLF energy interacts with living tissue. If certain individuals are more sensitive to this effect, they might “hear” these transmissions as a low hum, even though no acoustic sound wave is present. This would explain why microphones can’t detect the Hum and why only a fraction of the population perceives it. Researchers have attempted to test the theory using shielded enclosures designed to block VLF radio waves, though results remain inconclusive.
Geological and Atmospheric Sources
Another category of explanation looks at the Earth itself. The planet produces a constant background of extremely low-frequency vibrations called microseisms, generated by ocean waves interacting with the seafloor. These vibrations exist on a spectrum: seismic hum below 20 millihertz, primary microseisms between 0.02 and 0.1 Hz, and secondary microseisms between 0.1 and 1 Hz. Ocean infragravity waves, which are very long, slow-moving swells, create pressure fluctuations that reach the deep ocean floor and convert into seismic energy through interaction with underwater terrain.
At the very lowest frequencies, atmospheric disturbances can also contribute. Scientists describe the solid earth, ocean, and atmosphere as a coupled system, meaning vibrations can transfer between all three. While these natural frequencies are generally far below the 30 to 80 Hz range reported by Taos hearers, some researchers speculate that local geological conditions could amplify or shift these vibrations into the audible range for sensitive individuals.
Health Effects on Hearers
For people who perceive the Hum, it’s far more than a curiosity. The most commonly reported physical effects include headaches, nausea, diarrhea, fatigue, and memory difficulties. Because the sound is constant or near-constant and seems inescapable, the psychological toll can be severe. Hearers report intense annoyance, feelings of helplessness, chronic sleep deprivation, and in some cases, suicidal thoughts.
Much of the psychological distress stems from the nature of the problem itself. The source is undefined, uncontrolled, and invisible to most other people. Hearers often struggle to be taken seriously, which compounds the isolation. Unlike a noisy neighbor or a highway, there’s no entity to complain to and no obvious fix. Closing windows, using earplugs, or moving to a different room rarely helps, because the sound seems to bypass normal acoustic pathways.
A Global Phenomenon
Though the Taos Hum is the most famous case, similar reports have surfaced worldwide. Bristol, England saw a wave of complaints in the 1970s. Windsor, Ontario experienced a well-documented hum in the 2010s. As recently as November 2025, residents of Whitehorse in Canada’s Yukon territory reported a low mechanical humming that one person described as “repetitive and random.” The global pattern suggests the Hum is not unique to Taos or to any single local source like a factory or pipeline. Whatever the cause, it appears to be something more widespread, possibly involving a mechanism that affects susceptible individuals regardless of geography.
The Taos Hum remains one of those rare phenomena that sits right at the intersection of acoustics, neuroscience, geology, and electromagnetic theory. No single explanation has won out, and it’s possible the answer involves more than one mechanism. For the roughly 2% of people who can hear it, though, the experience is vivid, persistent, and very real.