Request for knowledge - Troubles at home

[nctnico]

The environmental protection limits are completely inadequate in this area. A limit of dB A weighted at the nearest residential boundary is common in Australia (hence the above questions about the specific zoning).

I agree. Over here low frequency noise pollution is getting more attention fortunately.

Off topic, but yet the Dutch government is working on laws to only allow hybrid central heating systems as a replacement from 2026 onward. Most of these systems use air to water heat pumps, which make noise. Imagine a "nice" vinex location or a town like Amsterdam with all the houses fitted with such units what a noise level that might bring.

Edit: It might be read as that every body had to get a new central heating system, so added "as a replacement". Only when you need a new one you have to install a hybrid.

More uninformed/irrational heat pump scare mongering! Australia has limits on domestic appliance noise, 45 dB(A weighted) at the boundary. With plenty of installs being built right on the boundary the majority of new heat pumps meet the requirements so its not even an extra cost. There are legacy heaters gas/oil/heat-pump that fail that limit too, but since the rules only apply to new installations they get away with it.

45dB(A) is rather loud especially if you want to sleep with the windows open. And as I wrote before: measuring in dB(A) is horribly wrong because it won't account for low frequency noise.

[Someone]

The environmental protection limits are completely inadequate in this area. A limit of dB A weighted at the nearest residential boundary is common in Australia (hence the above questions about the specific zoning).

I agree. Over here low frequency noise pollution is getting more attention fortunately.

Off topic, but yet the Dutch government is working on laws to only allow hybrid central heating systems as a replacement from 2026 onward. Most of these systems use air to water heat pumps, which make noise. Imagine a "nice" vinex location or a town like Amsterdam with all the houses fitted with such units what a noise level that might bring.

Edit: It might be read as that every body had to get a new central heating system, so added "as a replacement". Only when you need a new one you have to install a hybrid.

More uninformed/irrational heat pump scare mongering! Australia has limits on domestic appliance noise, 45 dB(A weighted) at the boundary. With plenty of installs being built right on the boundary the majority of new heat pumps meet the requirements so its not even an extra cost. There are legacy heaters gas/oil/heat-pump that fail that limit too, but since the rules only apply to new installations they get away with it.

45dB(A) is rather loud especially if you want to sleep with the windows open. And as I wrote before: measuring in dB(A) is horribly wrong because it won't account for low frequency noise.

That's at the boundary, not in your room. Its very quiet, and the absolute maximum upper limit for new installations (most end up quieter again). People walking around their house or having their TV on is louder.

[pcprogrammer]

The environmental protection limits are completely inadequate in this area. A limit of dB A weighted at the nearest residential boundary is common in Australia (hence the above questions about the specific zoning).

I agree. Over here low frequency noise pollution is getting more attention fortunately.

Off topic, but yet the Dutch government is working on laws to only allow hybrid central heating systems as a replacement from 2026 onward. Most of these systems use air to water heat pumps, which make noise. Imagine a "nice" vinex location or a town like Amsterdam with all the houses fitted with such units what a noise level that might bring.

Edit: It might be read as that every body had to get a new central heating system, so added "as a replacement". Only when you need a new one you have to install a hybrid.

More uninformed/irrational heat pump scare mongering! Australia has limits on domestic appliance noise, 45 dB(A weighted) at the boundary. With plenty of installs being built right on the boundary the majority of new heat pumps meet the requirements so its not even an extra cost. There are legacy heaters gas/oil/heat-pump that fail that limit too, but since the rules only apply to new installations they get away with it.

45dB(A) is rather loud especially if you want to sleep with the windows open. And as I wrote before: measuring in dB(A) is horribly wrong because it won't account for low frequency noise.

A neighbor of ours has a unit outside his house, and only when we walk by I can hear it, but this is 170M away from our house, so no biggie, but hang multiple of these units of building walls and who knows what resonance pattern comes to life.

Resonance is a bitch. When I still lived in the Netherlands it was in a rural village but across the road from our house was Nunhem zaden (now BASF) and they build a power house at some point. I started to hear the hum of it in our house and complained about it. They were very helpful and installed a special filter in the chimney of the power house, which solved the problem. During the time it caused us hinder I could hear it louder at certain points in the house due to resonance.

[Someone]

The environmental protection limits are completely inadequate in this area. A limit of dB A weighted at the nearest residential boundary is common in Australia (hence the above questions about the specific zoning).

I agree. Over here low frequency noise pollution is getting more attention fortunately.

Off topic, but yet the Dutch government is working on laws to only allow hybrid central heating systems as a replacement from 2026 onward. Most of these systems use air to water heat pumps, which make noise. Imagine a "nice" vinex location or a town like Amsterdam with all the houses fitted with such units what a noise level that might bring.

Edit: It might be read as that every body had to get a new central heating system, so added "as a replacement". Only when you need a new one you have to install a hybrid.

More uninformed/irrational heat pump scare mongering! Australia has limits on domestic appliance noise, 45 dB(A weighted) at the boundary. With plenty of installs being built right on the boundary the majority of new heat pumps meet the requirements so its not even an extra cost. There are legacy heaters gas/oil/heat-pump that fail that limit too, but since the rules only apply to new installations they get away with it.

45dB(A) is rather loud especially if you want to sleep with the windows open. And as I wrote before: measuring in dB(A) is horribly wrong because it won't account for low frequency noise.

A neighbor of ours has a unit outside his house, and only when we walk by I can hear it, but this is 170M away from our house, so no biggie, but hang multiple of these units of building walls and who knows what resonance pattern comes to life.

Resonance is a bitch. When I still lived in the Netherlands it was in a rural village but across the road from our house was Nunhem zaden (now BASF) and they build a power house at some point. I started to hear the hum of it in our house and complained about it. They were very helpful and installed a special filter in the chimney of the power house, which solved the problem. During the time it caused us hinder I could hear it louder at certain points in the house due to resonance.

Is that a modern quiet unit, or some older noisy one? What is its noise 1m from the source? how far away were you standing to it?
Some days I can hear small birds tweeting in the park 100m away, were they loud or was the environment very quiet?
When your neighbour is 170m away that sounds like a very rural/spread out area that would usually be a quiet environment to begin with.

"I once heard some noise from a heat pump" does not imply cities will become noisy if heat pumps become mandatory.

Like we say, there are noisy appliances, gas heaters can be equally as noisy as heat pumps. But modern noise restrictions have forced all the different heating/cooling options to be much quieter than they used to be (when they had no specific limits).

[tom66]

Most big cities in hot parts of the world have air con for apartments and houses, and besides faulty units I've never thought they were all that loud while running.

[pcprogrammer]

It is not a to modern unit, and it is no problem certainly with the big distance between the houses. That is why we live here.

When we are in the Netherlands even in the south (Roermond) there is a constant background noise of traffic and industry of some scale. With near 18 million people it is very crowded. Here within a village of ~100 people most of the time it is just nature. Which can also be very loud (birds, frogs, deer, cows, wind, etc.) but also very quiet.

Long time ago we went to America and flew into Las Vegas to start our trip touring that part of the states. For the first night we had a room in one of those casino hotels. Could not sleep due to the air-conditioning units on the roof. There was no quit spot in the room to be found. It might be that I'm very sensitive for noise, and even though I'm getting older my hearing is still good. Only in the top frequencies >6KHz my left ear is a bit below normal, for the rest still above.

And there in lies the difference, some people are sensitive to even the smallest sound, and others can sleep with a busy highway nearby.

[JohanH]

And there in lies the difference, some people are sensitive to even the smallest sound, and others can sleep with a busy highway nearby.

In the army I remember sleeping in a ditch behind the shooting range, waiting for my turn while the other fired on!

[IanB]

Most big cities in hot parts of the world have air con for apartments and houses, and besides faulty units I've never thought they were all that loud while running.

That's not my experience.

Could not sleep due to the air-conditioning units on the roof. There was no quit spot in the room to be found.

This.

In hotel rooms that have one of those window mounted or wall mounted aircon units, they are usually so noisy that I cannot sleep with them running. I have a choice of a cool room with too much noise, or a quiet room that is too hot. My usual strategy is to run the thing at max all evening, then turn it off before sleeping.

In residential neighborhoods with pad mounted central a/c units, they make an unmistakably loud humming and whirring noise. I can clearly hear when units in nearby houses switch on.

[tom66]

I think what this says more than anything is perception is everything.  Some people don't care whereas others the slightest sound while sleeping keeps them awake.  May even be the OP's problem.

When we were in Spain we stayed in a modern hotel which had central AC.  The rooms all had air handlers in them.  We had that on full power overnight and you could barely hear it yet the room was essentially a fridge.

The worst units are the non-inverter types due to the cycling.  The inverter units in my experience tend to be very quiet once they are 'up to power', and the 'ramp up time' is quite short (10-15 minutes.)

Even my car has a 24,000 BTU A/C system (plugin hybrid) and on full blast pulling 2kW from the battery, it's only noticeable if you're directly in front of the fan.  Otherwise, you can barely tell it is running.  That is a variable-speed compressor as well.

[CatalinaWOW]

You are aiming at some very low noise levels.  Weighting is an issue but there are real practical limits.  I live in a very rural setting where the tire noise of a single vehicle passing is quite obvious.  But the sound pressure is in the mid 30s of dB.  That residual noise is the rustling of tree leaves, insect calls and whatever.  Inside the house with windows closed it is lower by a few dBs.  Trying to lower noises below that is very challenging, which is why I earlier suggested masking.  Use a white noise generator (or one of those "soothing" background music channels) to create a sound (or vibration) level 10 to 20 dB above your problem.  Initially annoying the mind fairly quickly adapts and ignores lower level disturbances.

[nctnico]

Most big cities in hot parts of the world have air con for apartments and houses, and besides faulty units I've never thought they were all that loud while running.

That's not my experience.

Could not sleep due to the air-conditioning units on the roof. There was no quit spot in the room to be found.

This.

In hotel rooms that have one of those window mounted or wall mounted aircon units, they are usually so noisy that I cannot sleep with them running. I have a choice of a cool room with too much noise, or a quiet room that is too hot. My usual strategy is to run the thing at max all evening, then turn it off before sleeping.

Same here. I have fights with my wife over having the aircon on in hotels because they make too much noise for me to sleep well. Things get worse if the hotel room is in a bad position where you can hear the outside units. Definitely a reason to change to a different room.

At home I installed the quietest aircon I could find and mounted it the indoor unit in the hallway instead of in the bedroom.

[lxmute]

Hello,
Your replies were helpful to bring me back to the "sound aspect" problem.
Requesting help from a specialist in EMI and its derivatives, I've been led to the problem of Infrasounds generated by harmonics inducted by high power + high frequencies (moderated since in 90kHz range) at a low frequency range on unshielded city grid cables.

Sacrebleu! I think I'm in a deep sh?t to monitor this with accuracy.

[EEVblog]

Hello,
Your replies where helpful to bring me back to the "sound aspect" problem.
Requesting help from a specialist in EMI and its derivatives, I've been led to the problem of Infrasounds generated by harmonics inducted by high power + high frequencies (moderated since in 90kHz range) at a low frequency range on unshielded city grid cables.

Err, how do the city power cable induce low frequency sound? What is the physical mechanism?
Sorry to tell you, but it sounds like you have been peddled some BS 

[ebastler]

That's what I thought... Also, where is the 90 kHz carrier supposed to come from, with a 50 Hz power grid and mainly resistive loads in the bakery's ovens?

Sounds like that "specialist in EMI" might be someone who cashes in on people's diffuse fears of "bad electrical fields" by selling them some phantasy consulting services. Does he have a name and a website maybe?

[lxmute]

Err, how do the city power cable induce low frequency sound? What is the physical mechanism?
Sorry to tell you, but it sounds like you have been peddled some BS 

My query came from 2 assertions made on an industrial keynote about shielding,
« the higher the power, the bigger this EMI becomes »
« high voltage in addition to high frequency, you generate low frequencies EMI »
The doctor speaking was talking about high frequencies in general, producing some harmonics going into lower frequencies.
So I simply requested, if it can be possible, that on a high power source, a lower frequency that what you expect when saying high frequencies, some RF signal then, could also produce some harmonics, in a lower range, so very low range frequencies, so infrasounds, was a domain of possibilities. I received a firm confirmation.
90kHz is what I call "RF" here, since it's in the RF range field. Correct me if I'm wrong.

That's what I thought... Also, where is the 90 kHz carrier supposed to come from

http://scent-itn.org/emi_cenelec_freq.html

I will put efforts into improving my RaspiBoom noise cancellation. I also would like to put my hands on such device:
http://article.nadiapub.com/IJSIP/vol8_no9/22.pdf

If you need to visit a lovely place, Brittany is nice, and want to experiment the trouble by yourself, my home is open 

A last note, there is a bloom in France of people being hardly hit by infrasounds, on the whole territory.  Which ignited 2 years ago my curiosity.
and btw I'd just like to get back to normal things in my life. Coding, Woodworking, Sailing. Just a few months of stamina, I sold out my business and just quit the frogs country. 

the bakery's ovens

I would say the bakery still remains a possibility, but also a noise, or even a B Factor on a A+B problem.

[nctnico]

Hello,
Your replies where helpful to bring me back to the "sound aspect" problem.
Requesting help from a specialist in EMI and its derivatives, I've been led to the problem of Infrasounds generated by harmonics inducted by high power + high frequencies (moderated since in 90kHz range) at a low frequency range on unshielded city grid cables.

Err, how do the city power cable induce low frequency sound? What is the physical mechanism?
Sorry to tell you, but it sounds like you have been peddled some BS 

Pass enough current through a cable and it will start to move due to the magnetic field. Lookup some videos about arc melting furnaces. You can see the cables dance around. The same can be seen from cables going to spot welders. Heck, I even managed to make test leads move on my desk by discharging a capacitor bank causing a 1kA current spike. All in all it is possible that cables move or vibrate.

[ebastler]

That's what I thought... Also, where is the 90 kHz carrier supposed to come from

http://scent-itn.org/emi_cenelec_freq.html

Yes, power line communication is a thing. But those signals are not "high power". Even in the presence of non-linear effects, which could in principle generate sub-harmonics, I struggle very much to see how they could induce noticeable audible or sub-sonic frequencies.

You are barking up the wrong tree. The multiple earlier posts which were encouraging you to look into low-frequency vibrations, were trying to lead your thinking away from the EMI you were so concerned about. We were talking about the possibility of purely mechanical vibrations introduced from the bakery. You somehow managed to connect this back to your favorite concerns about EMI again, which I think is misleading you.

A last note, there is a bloom in France of people being hardly hit by infrasounds, on the whole territory.  Which ignited 2 years ago my curiosity.

Mass hysteria? 

(There's a peculiarity here with English, by the way. "Hardly" means "barely, not much at all". What you probably mean is that people were "hit hard" or "hit heavily" by infrasound. Although I believe that what you accidentally wrote, namely that they were "hardly hit", happens to be correct.  )

[nctnico]

That's what I thought... Also, where is the 90 kHz carrier supposed to come from

http://scent-itn.org/emi_cenelec_freq.html

Yes, power line communication is a thing. But those signals are not "high power". Even in the presence of non-linear effects, which could in principle generate sub-harmonics, I struggle very much to see how they could induce noticeable audible or sub-sonic frequencies.

You are barking up the wrong tree. The multiple earlier posts which were encouraging you to look into low-frequency vibrations, were trying to lead your thinking away from the EMI you were so concerned about. We were talking about the possibility of purely mechanical vibrations introduced from the bakery. You somehow managed to connect this back to your favorite concerns about EMI again, which I think is misleading you.

I agree with this. The problem is most likely to be acoustic. A good first step is to use vibration sensors to measure if, where and how the house is vibrating.

[Coordonnée_chromatique]

Hello,
Your replies where helpful to bring me back to the "sound aspect" problem.
Requesting help from a specialist in EMI and its derivatives, I've been led to the problem of Infrasounds generated by harmonics inducted by high power + high frequencies (moderated since in 90kHz range) at a low frequency range on unshielded city grid cables.

Err, how do the city power cable induce low frequency sound? What is the physical mechanism?
Sorry to tell you, but it sounds like you have been peddled some BS 

It seems to be a misinterpreted resurgence of a blurry souvenir : https://www.researchgate.net/publication/320106708_Low_Frequency_Oscillations_in_Large_Power_Grids

[lxmute]

Thank you, I will read this document.
Can a 65kV power grid transformer be considered as « high power », enough for this ?
I'm also wondering about neighborhood 20kV transformers.

Call me weirdy if you want, but there is a transformer 500m away, cables hidden into the ground. As the cable path is covered by new asphalt, you can clearly see its path. If I stand on that cables path, I feel under foot exact the same rythmic hassle as in my desk room.

As I'm wondering a bit about high power and how transformers are working, concerning all those neighborhood transformers, are they weighted by some barycentric law to handle a working stability altogether ?
Strange things happened in 2020 here, 3 walls just next to 3 transformers felt down. Then feb. 2020, the wall of a transformer just split in two parts, the 20kV transformer within exploded. 

I'm learning a lot by your objectivity, comments and doubts in the end, which is always good. Thanks.

[pcprogrammer]

It might depend on the amount of power being drawn, but we have a barn with solar panels nearby, which is connected via a transformer system (Big green cabinet with death warnings on it) to high tension lines. When I walk by I can hear the transformer (within a meter or three of the cabinet) but I can't feel any tremors in the ground when I walk on where the cables are in the ground.

So either a lot of current is running through the cables and they move so much that you can feel them or you are very very sensitive.

The smaller pole mounted transformers will probably make some noise but I don't hear the one that is next to our neighbors house, and I have sensitive ears.

[tom66]

I suspect any motion in the underground cables is damped by the earth's mass pretty quickly.

Exceptions would apply if they run close to structural members, for instance if a transformer pad was on the same pad as your building foundation.  I think that would be pretty odd, but some larger apartment complexes have their own mini substation/transformer inside them for residences.   And, in busy/dense urban areas they tend to build substations into similar looking properties, e.g. there are some of these in London that hide infrastructure for the Underground.

I think it's important to make measurements of any noise before assuming this is the cause though.  I'm still reasonably convinced this is psychosomatic -- that doesn't make it any less real to you but it means you won't fix it with a physical change unfortunately.

[lxmute]

Yes, it's a good point.
I'm currently reading a paper made by an acoustic office, a study for a nearby 65kV transformer in NE France. It's very complete and professional acoustic paper. I can't do that on my own.
« There is a time when you need to call for experts ».
I will spend more bucks, hiring such dedicated experts in noise measures. I'll keep you informed in the following months if curious about my case.

or you are very very sensitive.

let's have some fun, ex-wife told me I was way too much insensitive 

[EEVblog]

Hello,
Your replies where helpful to bring me back to the "sound aspect" problem.
Requesting help from a specialist in EMI and its derivatives, I've been led to the problem of Infrasounds generated by harmonics inducted by high power + high frequencies (moderated since in 90kHz range) at a low frequency range on unshielded city grid cables.

Err, how do the city power cable induce low frequency sound? What is the physical mechanism?
Sorry to tell you, but it sounds like you have been peddled some BS 

Pass enough current through a cable and it will start to move due to the magnetic field. Lookup some videos about arc melting furnaces. You can see the cables dance around. The same can be seen from cables going to spot welders. Heck, I even managed to make test leads move on my desk by discharging a capacitor bank causing a 1kA current spike. All in all it is possible that cables move or vibrate.

Yeah but he's talking about "unshielded city grid cables".
Are we supposed to seriously believe the "city grid cables" are physically vibrating and causing this guys sleep problems? Really? Nope, sorry, it's BS.

[EEVblog]

I will spend more bucks, hiring such dedicated experts in noise measures. I'll keep you informed in the following months if curious about my case.

Use you money to see a sleep medical specialist.
And like I said, start by buying a good well designed pillow.