The Sound and the Hearers
In the high desert of northern New Mexico, a small fraction of the population perceives a sound that defies explanation. First widely reported in the early 1990s, the Taos Hum is an acoustic anomaly heard by an estimated 2% of the local residents. Those who hear it, often called "hearers" or "hummers," describe a persistent, low-frequency drone. The character of the sound varies, with some describing a whir, others a buzz, and many comparing it to the sound of a distant idling diesel engine.
The reported frequency of the hum is specific, falling in the range of 32 to 80 Hz. Some hearers also perceive a modulation, a slight pulsing beat between 0.5 and 2 Hz. The phenomenon is often more intense indoors and at night, adding to its disruptive nature. For those affected, the experience is physical. Hearers report a range of physical symptoms, including pressure in the ears, headaches, dizziness, and nausea, which can lead to anxiety and sleep disturbances. The sound has been so distressing that some individuals have moved away from Taos to escape it, though a few report that the sound follows them.
The Scientific Hunt
The widespread reports prompted a formal investigation in the 1990s by a consortium of researchers from Los Alamos National Laboratory, the University of New Mexico, Sandia National Laboratories, and the Phillips Air Force Laboratory. This team deployed a comprehensive array of instruments in the homes of several hearers, attempting to isolate an external source for the sound. The equipment included sensitive acoustic microphones, seismometers to detect ground vibrations, and magnetometers to measure electromagnetic fields.
Despite the extensive monitoring, the investigation ended without a conclusive answer. The instruments failed to detect any single acoustic or vibrational signal that could account for the hum. Researchers explored numerous hypotheses. They looked for industrial sources, but no correlation could be found with local machinery or equipment. They investigated geological origins, such as microseismic vibrations, given Taos's location in a seismically active area, but no definitive link was established. The team also searched for electromagnetic sources, including the Navy's Extremely Low Frequency (ELF) communication system, but found nothing anomalous in the 65 to 75 Hz range. One study noted elevated electromagnetic field levels linked to the town's power lines, but this was not determined to be the cause.
With external sources proving elusive, some research has turned inward. One hypothesis is that the hum is tinnitus, a condition where a person perceives sound with no outside source. Another theory points to spontaneous otoacoustic emissions (SOAEs)—faint sounds generated by the inner ear itself, which up to 60% of adults have but are typically unaware of. It's possible that hearers have an unusually acute ability to perceive these internal sounds.