HELP! Anybody got any info on annoying low-frequency noise?

[RigidRaider]

My Mum aged 81 is being driven mad by a very low frequency throbbing noise, which she can hear at certain times of the day in her very old cottage. Others have heard it so tinnitus has been eliminated. A plumber thought it could be a fluttering ballcock valve and she has had the header tank valve replaced and the WC valves checked but still it goes on at certain unpredictable times. She is sleeping badly and taking tranquillisers now to help her cope. Environmental Health have been and dismissed it as "old folk" because the bloke couldn't hear anything at that time.

Because she lives five hours driving away down in Wiltshire I haven't been down but I plan to go next weekend and try to get to the bottom of it. I don't live there so I have no fear of nipping round to see the adjoining neighbour about their built-in fridge/freezer, their pond pump or whatever. It's either got to be some compressor or pump noise coming through the structure of the building or she is at the nodal point of some environmental noise (a company nearby makes frozen food and the refrigerated vans are parked up with compressors running) where sound waves are overlapping and producing harmonics.

Does anybody know anything about this kind of thing and does anybody have any literature I can read before I go? I am going to ask the Environment bloke to meet me there on Monday morning. All suggestions appreciated.

 

[rwhite]

My Mum aged 81 is being driven mad by a very low frequency throbbing noise, which she can hear at certain times of the day in her very old cottage. Others have heard it so tinnitus has been eliminated. A plumber thought it could be a fluttering ballcock valve and she has had the header tank valve replaced and the WC valves checked but still it goes on at certain unpredictable times. She is sleeping badly and taking tranquillisers now to help her cope. Environmental Health have been and dismissed it as "old folk" because the bloke couldn't hear anything at that time.

Because she lives five hours driving away down in Wiltshire I haven't been down but I plan to go next weekend and try to get to the bottom of it. I don't live there so I have no fear of nipping round to see the adjoining neighbour about their built-in fridge/freezer, their pond pump or whatever. It's either got to be some compressor or pump noise coming through the structure of the building or she is at the nodal point of some environmental noise (a company nearby makes frozen food and the refrigerated vans are parked up with compressors running) where sound waves are overlapping and producing harmonics.

Does anybody know anything about this kind of thing and does anybody have any literature I can read before I go? I am going to ask the Environment bloke to meet me there on Monday morning. All suggestions appreciated.

i believe this link can be of some help

http://www.environmental-protection.org.uk/noise/environmental-noise/low-frequency-noise/

 

[HH1]

The "Largs hum" could be on holiday down there.

 

[Nettybetty]

I am also being driven mad by a low frequency throb in Wiltshire near Pewsey. I have noticed it before but it has been constant now for nearly 2 days. It's a sound that is felt as well as heard and has been going all night as far as I can tell.
Anyone else hearing it? Or any suggestions? It doesn't seem to be a neighbours boiler that I can find. Internet searches return lots of UFO pages but I can't help feeling that the cause is earthbound and mechanical!!

 

[Big Tone]

With these things, the best way forward is always by process of elimination I think. I used to be an electronic engineer and fault finding was a big part of what I did. So go around switching things off one at a time and listen for whether it's stopped or not; the chances are the source of it is something electrical rather than purely mechanical. Therefore, if it's electrically powered you can switch it off. (Stating the obvious).

The mains frequency is 50 Hz, (cycles per second), which is audible if the guilty piece of equipment is faulty or badly designed. Is this the type of sound you can hear?

I once had an electric fire which had an induction motor turning a worm gear to create the illusion of flames and the noise was just terrible; made all the worse because it was on a hardwood floor which acted as a diaphragm. As you say, if it’s emanating from another house it could be difficult to locate but the neighbours will hopefully be cooperative. (It’s in their interest to get it fixed too after all). You could tell them sometimes it’s an indication that something’s about to fail Start by switching the whole house off in turn, beginning with your mother's of course. Sorry if I’m teaching my grandmother to suck eggs.

Next week, the scoop on how my ex wife ran off with my best friend. Hec, I really miss him...


Add: Just remembered! One house I lived in had a central heating 'chudder' which, on occasion, would go into a full blown stir-fry-crazy shake rattle and roll! (Air lock, I think I was told). You may need to use your sense of touch as much as your hearing to find it. Good luck

 

[wotan]

Are there any factories in the vicinity? I ask this because the chemical factory that I use to work at had a big stuvernt extractor fan coupled to a gas scrubber which then exhausted to a very tall stack, if the fan was left running with the plant shut down it acted like an organ pipe and could be heard several miles away, as a very low frequency hum.
We got reported and the environmental health officer, recorded the noise with an audio meter, we got issued with a warning notice, that any further infringements would result in a fine.

Wotan

 

[rjm2k]

Have you eliminated any electrical source in her home? If she's happy to, she could turn the main power switch off next time it happens to see if it's something of hers.

Also, same for the water, maybe turning off the stopcock to see if it goes away? Maybe if she can put her ear upto any pipes (not hot ones obviously)/radiators to see if it's louder.

In the meantime, can she sleep if she leaves the radio on low volume? Sometimes distraction can help to hide noise.

 

[Big Tone]

In the meantime, can she sleep if she leaves the radio on low volume? Sometimes distraction can help to hide noise.

Maybe a pair of these Or just ear plugs.

Doctor doctor, I keep hearing green green grass of home in one ear and Delilah in the other. Is it very common?

And the doctor says... Well - it’s not unusual.

 

[longdogs]

There was a whole thread on this subject a couple of years ago in GD where it seemed that quite a few people were experiencing this strange noise. I was woken up one night by what sounded like a car idling outside my house. After about an hour of it, I decided to take a look but there was no car there. I ended up checking all over the house, inside and outside at two in the morning. Although the noise was quite loud at one point, I was not able to pin point it. I went back to bed, stuck some cotton wool in my ears and tried to get back to sleep but could still hear it (feel it). So far, the noise has not returned since that night. There were also some instances reported on the news too.

 

[foxhole]

I am also being driven mad by a low frequency throb in Wiltshire near Pewsey. I have noticed it before but it has been constant now for nearly 2 days. It's a sound that is felt as well as heard and has been going all night as far as I can tell.
Anyone else hearing it? Or any suggestions? It doesn't seem to be a neighbours boiler that I can find. Internet searches return lots of UFO pages but I can't help feeling that the cause is earthbound and mechanical!!

central heating pump.
Bottle of Scotch can eliminate noise, take one large glass before bed.

 

[ntb]

In addition to noise from machinery and electrical transformers you can also get low frequency noise from enclosed spaces being resonated by the wind (think blowing over the end of a bottle). If you can find a correlation with wind intensity or direction this is something to investigate further.

Keep in mind that low frequencies propogate a very long way. The cause is not neccesarily in the vicinity. I think your best tactic is to figure out exactly when it started and what (if any) pattern can be discerned.

I had a hum once that seemed to come out of the blue. It actually built up and resonated a bedroom radiator yet when you damped the rad, it was barely audible. Eventually, I figured out it began at the same time as some bridge repairs half a mile away and started just after 8AM. The hum ended with the repairs.

 

[KenGMac]

Are there any Wind farms anywhere near?

As has been posted, low frequency can travel a massive distance.

for example in olden days a Submarine could detect "ultra low radio frequencies" by towing a one mile long copper wire out behind the boat when submerged at about periscope depth.

The transmitter could almost be on the other side of the world