Low frequency, under 40 Hz, sounds like an industrial air compressor running, shutting off briefly and randomly, and running again. Not a continuous sound sensation, and the pitch does not seem to change. It has somewhat of a "diesel motor sound" to it. My personal theory is that the sound sensation is not an external sound source at all, but an internal source, e.g., brainwaves sensed as an auditory signal, or perhaps the brain's response to the earth's magnetic field or the Sun's solar wind beating on the planet's magnetic field (picture the Northern Lights and how the pattern changes with time). Maybe the solar wind causes the atmosphere to pulse or vibrate at low frequencies.
What they reported
First noticed: Before 1990
Pitch: Under 40 Hz
Loudest: During the night
Where: Indoors
Symptoms: No symptoms of any kind
Changes with weather: No, but I notice it more at night in the winter months.
Constant Low hum. Like a truck idling. Intermittent where is seems louder or more intense within seconds. Almost like a revolving speaker? Curious if certain blood types hear it more than an…
Sounds as if a 4 to 6 cylinder diesel engine running in the distance. I disconnected my electrical power to the home once to test if the Hum is being generated by the power grid. It made no …
loud hum, almost like machinery droning in the background or a dryer running at a car wash - but at night when everything is closed. I've gone outside trying to figure out where it is coming…
Its a low, rhythmic humming that I hear at night and doesn't seem to go away. I specifically hear it in my bedroom, but not my living room, kitchen, hallway, or bathroom. I put my ears aga…
Low frequency humming noise. The frequency of the hum doesn't change, but there is a subtle pulsation associated with it. In a household of five, I'm the only one who hears it. I've been hea…
Continuous Low Frequency hum... maybe 120 hz, sometimes accompanied by a very low frequency, slow rumble ~30 hz. Was near a dynamite explosion once... also directly under a 3" artillery piec…
Usually starting at around 10pm, low frequency sound similar to that of an idling Diesel generator is perceived in my left ear. If sounds as if the source is external to the ear. However, I …
the accounts read alike, found by meaning rather than by shared details
Sounds like a train engine idling in the distance. It's a very low, rumbling. It is intermittent. It mostly drones at the same level, but occasionally pulses without a discernible pattern …
the accounts read alike, found by meaning rather than by shared details
A very low frequency oscillating sound like a constant running large diesel engine in the distance. I have looked into this topic online, as well as trying to figure out what could be causin…
the accounts read alike, found by meaning rather than by shared details
Has this happened to you?
Write it down while you still remember the details. We will look for the others.
If this reminds you of something a friend or a relative told you once and never mentioned again, send them this page. Reading that a stranger described the same thing is usually the part that helps.
Nothing is tracked back to you and nothing is sent on your behalf. The link is just the page you are reading.
This is a Hum report from Dr Glen MacPherson's World Hum Map, an open, worldwide record of people who hear an unexplained low-frequency hum. Reproduced with permission and with thanks; the project is at thehum.info. We remove anything on request. Location shown is approximate.
Anomaly