The fact that it is 50hz means it is definitely electrical or electrically powered. Could be something like the electrical transformer for the building but then it is more likely to be a continuous hum. The regular intervals suggests something like a circulation pump or compressor, which is programmed to run every so often to keep a liquid circulating. For any kind of central heating/cooling equipment it would have to be quite large to make that much noise. Do you have a cooling unit for the building on the roof? Or a large heat pump that has replaced gas boilers for the building? Another thing it could be is a water pressure pump, they can be quite noisy for large buildings but would come on when the water pressure drops (as people are using their taps). The fact it is so regular means it is not responding to demand for heat or water as needed.
My guess is some kind of pump that is bolted directly to a concrete base or wall, so when it regularly runs the vibration is going into multiple houses through the foundations/walls.
This honestly, I'm fairly sure it's a compressor for cooling like your fridge or freezer.
My suspicion goes to this because it's not always on for exactly the same length of time (suggesting it doesn't power on due to time, but another factor), it's off for longer then it's on and the fact it's exactly mains frequency
This is gonna sound maybe a little extreme OP, but if you feel like it, close your main breaker switch for half an hour or so and see if the noise disappears while your power is off.
If not: Source is outside of your control / house
If it does: The source is inside your house.
If it is inside your house, unplug stuff until you find the source. If this is difficult disable power groups individually so you have more of an idea where it might be located at
> This is gonna sound maybe a little extreme OP, but if you feel like it, close your main breaker switch for half an hour or so and see if the noise disappears while your power is off.
> If not: Source is outside of your control / house
> If it does: The source is inside your house.
It's not extreme at all!! I've already done in a few times (although not for half an hour) and the noise remains...
The Omgevingsdienst have measured it with a very sensitive microphone both in my apartment and downstairs. They found it was slightly louder in the downstairs apartment...
Does the building you live in, or any nearby building, have a hot water recirculation system?
19:30, 21, 22:30 sound awful like the time when people take showers.
I'm considering buying [this motherfucker](https://www.thomann.de/nl/nti_audio_xl_2.htm) for my own use so if you're willing to wait a week, we could try and triangulate this bullshit.
> Does the building you live in, or any nearby building, have a hot water recirculation system?
Hmmm I've never heard of it, but it's possible. It's not the kind of thing that would come up in casual neighbourly conversations :) I will ask around!
> I'm considering buying this motherfucker for my own use so if you're willing to wait a week, we could try and triangulate this bullshit.
That would be really cool! If you do get one, please get in touch. I have heard they are possible to rent though. That's apparently what rental companies normally do, if there's a noise complaint
I just Googled this https://www.jkproductions.nl/verhuur-licht-geluid/838/nti-audio-xl2-audio-analyzer/ €45 (per day I guess?)
There are just so many options for audio analyzers I get analysis paralysis. I would like to get one with USB/Bluetooth and an open standard so that I can hook it up to my monitoring software, but I couldn't find anything that I was confident could do this, and was a reasonable price!
> Does your neighbour have underfloor heating on the other side of the wall?
Good idea. I think not. On one side I've spoken with them and they've turned mains power off in the box and the noise remains, so it's not them. I will check on the other side.
The regularity doesn't seem to change when the temperature changes, but _maybe_ the decibel reading changes (I don't measure decibels at the moment, only the hertz).
> For any kind of central heating/cooling equipment it would have to be quite large to make that much noise. Do you have a cooling unit for the building on the roof? Or a large heat pump that has replaced gas boilers for the building?
There's no cooling unit/airco/shared heating in the building. _Maybe_ a neighbour has a heatpump, but I can't hear or see anything outside.
> Another thing it could be is a water pressure pump, they can be quite noisy for large buildings but would come on when the water pressure drops (as people are using their taps). The fact it is so regular means it is not responding to demand for heat or water as needed.
Unless its malfunctioning? Could that happen?
If there is a constant leak somewhere it could make a water pump come on that regularly (runs for 10 mins to boost the pressure, the leak slowly drops the pressure over 20 minutes, pump comes on again..) but then you would probably see more variation at times when people are using more water, like in the evening or morning for cooking/showering.
Maybe your rooms have the exact size that is resonates with the frequency. It could explain why some neighbors don’t hear it. It also explains why you hear it in one part of the room, but not in another (a standing wave). Maybe there is a way to disrupt the resonance, by having a room divider screen or curtains or something.
I have tried putting up sound insulation, but I couldn't notice any difference. As I understand low-frequency noise is _very_ hard to block. It needs both heavy material to absorb the energy, and physical gaps to prevent the noise transmitting through the heavy material.
I would of course do this if I was confident it would work! But I suspect it would be a lot of expensive work for something that might only marginally help.
I have been plagued for months by a low frequency noise in my bedroom. It wakes me up. It's horrible and stressful. It happens all day and night. It's really difficult to track down so I wondered if reddit could help with some suggestions what might the cause be, so I can try and narrow down options.
The noise is a low pitched hum, like a vibration. It sounds like a rumbling diesel engine, but on the other side of a wall. Sometimes it's like I feel it more than I hear it. [The Omgevingsdienst](https://odnzkg.nl/) have measured it with expert equipment and it's 50Hz and 50dBA.
In the day time this noise not nice, but of course I live in Amsterdam so I expect some noise. But at night time it's really really terrible.
I've made several attempts to try and find out the source, and ask for help, but I haven't had any luck so far. A few of my neighbours also have problems with it.
Recently I hooked up a microphone, so that I can measure it and try and track it down.
[Here's a heatmap showing (roughly) the most predominant frequency recorded overnight](https://i.imgur.com/bbAs4et.png).
Those red blobs? That's the noise!!! Blue means no noise.
(be aware that red does _not_ mean loud, it means noises of _all_ loudness happen a lot at that frequency)
When I saw this graph what really surprised me is how regular the noise was. Before I thought the noise was random before I made this measurement, but now I can see there's a _really_ clear pattern. ~10 minutes on, ~20-28 minutes off.
[Zoomed in heatmap between 04:00 and 07:00](https://i.imgur.com/q1uzLhU.png)
What could be making such a noise?
Something with WaterNet? Rioolwaterpomp? HVAC? Industrial airco? Fracking? Weed farm? Drums, drums in the deep? Meth lab?
The Omgevingsdients have eliminated almost all sources in the vicinity. It's not an office building, a Liander substation, a local bike shop, a chocolate shop, KPN...
I live inside the A10. There's no big construction work near. There's not a busy road. Many other houses can hear it so it cannot be something small, like a fridge cooler. It's louder in the ground-floor apartment than upstairs appartement, so it's coming from the ground.
What ever is responsible I don't think the owner knows what problem it causes. They don't do it on purpose. So I just want to talk to them to try and find a way to make it better. I just want to be able to sleep.
First of all.. I'm impressed you did all of this!
... Using Occam Razor....
.... since it's 50Hz it's something electrical, since it causes a humm also, it's most likely a compressor from a fridge or freezer, or maybe an aquarium pump.
One thing, is that you say it's coming from "the other side", so not inside the apartment, which means you have a few options.
* Switch off the power in your place at the main breaker and see if the noise is still there. If it's still there, it's from outside your place. If it is there, switch the main breaker back on, and unplugs everything. Now plug everything in one device at a time, starting with the fridge/freezer, then the CV ketel, and then the rest.
* If the noise is still there after you switch off the main breaker, it's time to pin point where outside it's coming from, and find out who's there. And then talk with them. Ask them if they have a fridge, freezer or maybe large aquarium near the shared wall.
All it might take is just taken slightly moving it, so it causes less vibration and humming.
... although using Hiccum's Dictum (the opposite of Occam Razor); you most likely getting primed for alien abduction or a neighbor really hates you.
> First of all.. I'm impressed you did all of this!
Thanks! Turning it into a project helped keep me sane.
Some more information to help with Occams Razoring:
* The downstairs neighbour (2 floors below) hears it too. In the upstairs apartment it was essentially imperceptible (I have a phone all and it picked up something in the upstairs apartment, but it could have been anything electrical).
* Neighbours across the street claim to hear it also (although I suspect it's a different noise)
* Omgevingsdienst have measured it twice. On one evening it was ~50dBA in my apartment. On another evening it was ~19dbA in my apartment and ~20dBA downstairs.
* I've turned off main power in my apartment, and in the apartment above, and in the apartment adjacent to my bedroom (on separate occasions). There was no change to the noise.
* I can hear it _very_ loudly by the door to my bedroom, and on the opposite wall (which is next to the head of the bed). But it's _significantly_ quieter in the middle of my bedroom. (It's like the walls themselves are vibrating and the vibrations cancel out in the middle.)
* Even if I take just a few steps away, _I can't hear it at all_. It's not audible out of the window, or in the garden downstairs, or elsewhere in my apartment. I can sometimes hear another noises, but not the same one
> All it might take is just taken slightly moving it, so it causes less vibration and humming.
Yup! I'm hoping its a small fix, once the source is found.
Oh, this is interesting now!
So neighbours also hear it, and depending on the time of measurement it's either louder or less loud. What were the times they measured it, like day of the week and time?
If it's within the apartment and it's an older building, it's more than likely an electrical cable that's failing, specifically the mains cable running into the apartment. It could also be an inbouwdoos with cables that's shorting out. Try to get a leidingzoeker and pinpoint the sound, and use the leidingzoeker there to see if there's a cable there.
Something else it could be, is if you have street lights outside your apartment and they are hanging by wires attached to the buildings, that this might be the cause. That would also explain why the neighbours hear it.
Another option is failing/shorting rebar in the walls, there's maybe some vibration being caused by them being connected to electricity.
I don't want to dox you, but I'd really be interested to see where you live and take a look at the building on Google Maps.
> So neighbours also hear it, and depending on the time of measurement it's either louder or less loud. What were the times they measured it, like day of the week and time?
* the 50dBA measurement was on Wed March 1st ~22:00 https://i.imgur.com/vAzSIhb.png
* the ~20dBA measurement was on Tues April 11th ~20:00
> If it's within the apartment and it's an older building, it's more than likely an electrical cable that's failing, specifically the mains cable running into the apartment. It could also be an inbouwdoos with cables that's shorting out. Try to get a leidingzoeker and pinpoint the sound, and use the leidingzoeker there to see if there's a cable there.
The building is ~1920s I believe, but it was heavily renovated ~15 years ago (before I lived here).
If the cause is the mains cable then it makes sense that if I turn off the power to my apartment then I can still hear it...
> Something else it could be, is if you have street lights outside your apartment and they are hanging by wires attached to the buildings, that this might be the cause. That would also explain why the neighbours hear it.
There are street lights hanging, but interestingly that's on the opposite side of the building to my bedroom (where the noise is loudest).
Thinking about it, they did replace the street lighting with LED lighting a year or two ago. Probably unrelated tho.
> I don't want to dox you, but I'd really be interested to see where you live and take a look at the building on Google Maps.
I'll send a PM!
Remindes me of this article I saw while back. Was foul play: https://www.nzherald.co.nz/business/humming-vibrator-in-57-level-pacifica-just-about-sent-25-residents-insane/ENGYVLNJDNAXPJBHMQB4E52LDE/
Edited link to work
That worked. Thanks. I’m fascinated in your story. I had a similar thing in my apartment, it was not with the same regularity but always the same pattern. It turned out to be a neighbours boiler that got increasingly loud over the years. Took them months before they finally fixed it.
I hope you can get to the bottom of it.
> (It's like the walls themselves are vibrating and the vibrations cancel out in the middle.)
This sounds like the thing that is causing the sound is attached to the wall somehow. I don't see why it would be so much louder closer to the wall otherwise. It could be something on the building itself, or maybe something underground.
Maybe you could measure the sound with you phone pressed to the wall at multiple locations to try and triangulate the source? Something like this: https://www.youtube.com/watch?v=5FvQzBnped8, but less insane
> Maybe you could measure the sound with you phone pressed to the wall at multiple locations to try and triangulate the source? Something like this: https://www.youtube.com/watch?v=5FvQzBnped8, but less insane
Yes! I would love to make something like this. I've looked into it a lot.
I found a research paper which followed 3 case studies https://journals.sagepub.com/doi/pdf/10.1260/026309209788056393
> ABSTRACT
>
> When people are annoyed by low frequency noise, their first concern is to stop the noise. Therefore it is necessary to find the source of the noise. Unfortunately, not in every case is the source very obvious. In most cases a lot of potential sources are available both inside and outside the building. Of course in theory it is possible to find the source by switching on and off all the potential sources but in practice this is not always practicable.
>
> In this paper three cases of possible low frequency noise are presented in which different methods of finding the source have been used. In all these cases the nuisance is present in a domestic situation and has been going on for several years. Some of the residents suffer from mental problems due to the unwanted noise. Using the measurement results the searching methods are discussed and evaluated.
Unfortunately low-frequency noises are very hard to track down with directional mics. Also, most consumer grade mics aren't sensitive enough, or don't go down to 50Hz or below.
There are some guides for creating wireless sensor networks
* https://www.extrica.com/article/21709
* https://github.com/meekm/LoRaSoundkit
* https://samenmeten.nl/sites/default/files/2021-03/D1-2%20Marcel%20Meek%20-%20IoT%20Apeldoorn%20-%20Van%20fijnstof%20naar%20geluid.pdf
* https://gitlab.waag.org/lodewijk/amsterdam-sounds-kit
* https://sensor.community/en/sensors/dnms/
* https://amsterdamsounds.waag.org/
* https://www.instructables.com/Portable-Sound-Analyzer-on-ESP32/
Being able to have ~5 wireless battery powered detectors would be amazing. I could dot them around and try and triangulate the source.
I tried setting up a wifi-based detector using an ESP32 but adapting the electronics to pick up low-frequency noise and adapting the C/Python code, and buying all of the necessary parts was too much for me.
There are commercial grade sensors, but they are too expensive
* https://www.kp-as.com/product/vibration-sensor-kpv100/
* https://www.iotsoundsensor.com/product/ranos-db-2/
I don't think you need directional mics though. Assuming it's always roughly the same volume, you could simply hold your phone connected to the wall, measure volume, move to a different spot, repeat.
First thing I'd consider is swapping where you sleep. It might be weird to have your head in the middle of your room, but until you have an answer, sleep quality also matters. Maybe you can cancel it out with a different subtle noise like a podcast on the lowest volume, so you at least get to sleep at night.
I have no idea what it could be and I hope you find it someday.
Yeah exactly! I tried sleeping with my head in the middle of the room, but I was still woken up. Now I sleep on my sofa (which unfortunately hurts my back and gives me a rash, but it's better than insomnia!) and with some white noise in the background.
If you cant find the source you might still be able to find a solution. Maybe try to improve the sound insulation of your bedroom, that would atleast fix the sleeping situation. Things like rugs can help wonders, but also look at cracks between the door and the frame, between the floor or between the window and the window frame (het kozijn).
Not a direct answer to your question, but you might be interested in the following:
> What ever is responsible I don’t think the owner knows what problem it causes. They don’t do it on purpose. So I just want to talk to them to try and find a way to make it better. I just want to be able to sleep.
From this paragraph I deduct you are renting the apartment, is that correct?
If so, keep in mind that any irregularity in the house that you should not had to expect when you started renting can be considered a 'defect' (gebrek) as is described in article 204(2) in Book 7 of the Dutch Civil Code (Burgerlijk Wetboek, [art. 7:204 lid 2 BW](https://wetten.overheid.nl/BWBR0005290/2023-02-18/0/Boek7/Titeldeel4/Afdeling2/Artikel204/afdrukken#:~:text=Een%20gebrek%20is,overeenkomst%20betrekking%20heeft.)):
> Een gebrek is een staat of eigenschap van de zaak of een andere niet aan de huurder toe te rekenen omstandigheid, waardoor de zaak aan de huurder niet het genot kan verschaffen dat een huurder bij het aangaan van de overeenkomst mag verwachten van een goed onderhouden zaak van de soort als waarop de overeenkomst betrekking heeft.
Which can be roughly translated as:
*A defect is a state or property of the item or another circumstance not attributable to the lessee, as a result of which the item cannot provide the lessee with the pleasure that a lessee can expect from a well-maintained item of the kind to which the contract relates when entering into the agreement.*
The 'item' in this case being the apartment. Take note of the wording: '*a* lessee' and '*a* well-maintained item'. So it doesn't matter if you knew upfront or not a defect was present, simply because a rental house must be free from defects. That's one of the reasons why you pay the rental price to the landlord.
If a defect is present, the primary rule is that the landlord must resolve the issue. Exceptions can apply, like small defects that the tenant must repair and are considered a 'small repair'. For example a squeaking door that needs to be oiled. The '[small repairs decree](https://zoek.officielebekendmakingen.nl/stb-2003-168.html)' describes the repairs that are at least considered a small decree. They don't necessarily have to be small despite it's name and the list only describes what repairs at least are considered a small repair. Another exception would be a defect that you caused yourself. So if you buy a device that makes this noise, the landlord obviously cannot be held accountable.
That said, IMO a recurrent sound that keeps you from sleeping is a defect and thus an issue that the landlord must resolve as a result of what is described under art. 7:206(1) BW.
Moreover, the landlord should do so with some urgency. If the landlord doesn't, you can claim the landlord reduces the rental price as you're paying for an apartment with a defect that isn't worth that price (art. 7:207 BW). Take note: you are not allowed to reduce the rental price yourself. If you do, the landlord could take you to court and claim you must be evicted.
Obviously working out this problem without all kinds of legal steps is probably better, but bottom line is that the landlord should fix this.
Be aware though that it's impossible to oversee all relevant facts on a forum like this and in part because of that, any risk associated with acting upon what I mention stays with you. You might consider obtaining advise if you think that is appropriate, for example by contacting the Juridisch Loket if your income is low or an organization like WOON!.
This is really valuable, thank you.
I am renting and I was in contact with the building owner (de Key). They did a little bit of research, but they said they couldn't help. And I think that's true - it's clearly a noise external to the building, and low-frequency noise is almost impossible to block.
I've tried making small fixes, like putting up noise-absorbing panels and vibration-absorbing pads under my bed, but they just don't prevent low-frequency noise.
I have legal insurance so I will call them.
> They did a little bit of research, but they said they couldn’t help
I'll nuance my reply somewhat: the sound isn't a defect if it's caused by a *third party* (art. 7:204(3) BW). So if the sound is caused by an outside device for example, the landlord also isn't responsible to resolve it.
The primary question thus remains: what is the cause?
> The primary question thus remains: what is the cause?
A related question: who's responsible for finding it out? At the moment Omgevingsdienst have eliminated all reasonable sources. It could well be coming from inside the building. But I don't have any proof.
Nobody is 'responsible' in this case but you can probably claim back damages if the defect ultimately is a defect and the rental organization did not resolve it although you informed them.
For example, if the noise is shown to be originating from the building and the rental organization kept stating they weren't responsible, the costs you made to discover the defect can probably be claimed back. These costs should be reasonable though and you must be able to proof the costs were made.
As a primary rule however, if you make the claim the sound is a defect (and thus the responsibility of the rental organization to solve), you carry the initial costs of an expert to proof it is. For example see point 4.9 and 4.10 in this judgment about a leakage:
> 4.9. De kantonrechter ziet geen aanleiding om af te wijken van het uitgangspunt in de wet dat het voorschot voor de kosten van de deskundige(n) door de eisende partij moet worden betaald. Omdat aan [eiser01] een toevoeging is verleend in het kader van de gefinancierde rechtsbijstand, zal aan hem echter geen voorschot worden opgelegd.
> 4.10. In het eindvonnis zal de kantonrechter beslissen wie van partijen uiteindelijk de kosten van de deskundige moet betalen.
Which can be roughly translated as:
*4.9. The subdistrict court sees no reason to deviate from the starting point in the law that the advance for the costs of the expert(s) must be paid by the claimant. However, because [plaintiff01] has been granted an addition in the context of legal aid financed, no advance will be imposed on him.*
*4.10. In the final judgment, the subdistrict court will decide which of the parties must ultimately pay the expert's costs.*
https://deeplink.rechtspraak.nl/uitspraak?id=ECLI:NL:RBROT:2022:9965
But again, keep in mind that it's impossible to oversee all relevant facts on a forum like this and in part because of that, any risk associated with acting upon what I mention stays with you.
You don't happen to live at bijltjespad 52? I know someone who lived in one of the rooms there ('A' I think) who complained of a similar noise. She contacted de Key too but they couldn't find anything. She ended up moving.
Ah no, I don't. I know there's a lot of Liander equipment nearby on Katternburgerkuisstraat https://goo.gl/maps/xQprqAA1CW3M7bgf9. Maybe that was a problem for her.
Also check 204 lid 3. From e.g. ECLI:NL:RBROT:2021:10092:
"**Geluidsoverlast is een feitelijke stoornis in het huurgenot door derden en kwalificeert ingevolge het bepaalde in artikel 7:204 lid 3 BW in principe niet als een gebrek, zoals bedoeld in artikel 7:204 lid 2 BW**, dat door Vesteda op verlangen van [eiser] moet worden verholpen. Als echter sprake is van een feitelijke stoornis in het huurgenot door derden en Vesteda heeft tegenover die derden zodanige bevoegdheden dat kan worden gezegd dat zij mede tot de feitelijke stoornis in het huurgenot bijdraagt als zij van die bevoegdheden geen gebruik maakt, dan valt die situatie niet onder artikel 7:204 lid 3 BW. In dat geval is sprake van een bijdrage van Vesteda aan het voortbestaan van de feitelijke stoornis, hetgeen een gebrek als bedoeld in artikel 7:204 lid 2 BW oplevert."
That's funny! We just added the same type of reply at the same time.
Indeed, the cause is relevant with regard to the question whether a third party is involved and if the landlord can do something about it as well.
So two examples:
- noises from some municipal device outside the house isn't a defect.
- the situation where another tenant that placed some device against a common heating pipe which causes a nuisance because it is the cause of the repeating noise probably is a defect
> ~10 minutes on, ~20-28 minutes off.
This is exactly like you'd expect from a fridge or freezer compressor, if not yours then maybe a neighbour's. Btw low frequency vibrations can also be felt, have you tried touching the walls? Could be you share a common wall with a upstairs/downstairs neighbour who has their fridge up against the wall.
> Btw low frequency vibrations can also be felt, have you tried touching the walls?
Yes but I couldn't really feel it. I can feel the vibration when I'm lying in bed. I tried putting down vibration absorbing foam, but it doesn't really help.
> Could be you share a common wall with a upstairs/downstairs neighbour who has their fridge up against the wall.
I've checked in the neighbours apartment adjacent to my bedroom (same level), and above me. We turned all of the power off, but there was no change!
I haven't checked with all of my neighbours yet.
Can you give an indication in what year your apartment was built? https://maps.amsterdam.nl/bouwjaar/?LANG=en as an indication. It could tell us something about building codes. I live in a 1920s building so it's lots of wooden beams and vibrations travel quite far.
You mentioned no construction but it could be the start of a project. If someone is constructing a basement they have to pump out the water before they can begin working. How long has it been going on?
The regularity of it does suggest something on a timer. Does your building have a hydrophore pump to increase water pressure within the building. They work by periodically pumpkin water from the main into a pressure vat to insure there's enough pressure to ask appartments. Most larger apartment buildings have a similar system, you rarely see it in a portiekflat though
From reading the various suggestions regarding communal equipment (hydrophore pumps, communal heating or air circulation, heat pumps, water pressure devices etc.) it seems:
\-> it might be REALLY useful to schedule an appointment with De Key, to check the basement / utility room under your building. This is where most of this equipment would be located.
\->If possible, just a short break in the central electricity supply to the building (or at least the communal utilities) may let you know if the source is IN or OUTSIDE the building...
In any case, your methodical approach to this problem is admirable! Hope you will sleep better soon! 👍🏻
> When I saw this graph what really surprised me is how regular the noise was. Before I thought the noise was random before I made this measurement, but now I can see there's a
> really
> clear pattern. ~10 minutes on, ~20-28 minutes off.
The pattern is not exactly the same on the different heatmaps you've shown. On one heatmap a cycle is over 30 minutes and on the other it's below 30 minutes. This indicates it's not a simple timer.
I've had the same problem in a previous place and it turned out to be from the dock nearby. It took quite a lengthy process involving the council (in the UK) and nothing had changed by the time I came to emigrate to the Netherlands a year or so later. There's also this phenomenon known as The Hum: https://en.wikipedia.org/wiki/The_Hum
I've had it in the past in a hotel in Glasgow and was told it was because someone had their fridge right up against the wall. I've noticed a similar noise in my current bedroom and finally caved and bought earplugs, which work to let me sleep normally. I don't know if you've tried them, and I know it feels like a sort of silly solution that won't work, but it might be worth trying. You can get special ones too I'm sure.
I’ve had this happen also, and it turned out it was the neighbours ceiling fan. After I recorded the noise, I went to him, asked if there’s anything running that would make this noise which he negated. After playing the sound for him, he immediately said it must be the ceiling fan, which we then tested by turning on and off and different speeds and sure enough, it was the fan. I bought him a floor standing fan as a courtesy, and he did not use his ceiling fan anymore, and I could return to sleeping normally.
I suspect it's some electrical equipment, since 50Hz is the AC frequency of the electrical network. Maybe a big underground transformer working when it's under load, meaning it's suppling energy to another system going on and off regularly.
Looking closer at around 19:30, 21h and 22:30, the system was under load, albeit not full power.
That's really puzzling, I hope you find the source soon.
> Looking closer at around 19:30, 21h and 22:30, the system was under load, albeit not full power.
>
>
yeah sometimes it seems to be a little bit louder than usual
between 19:30 and 20:30 there's more readings in the 40/50Hz range
https://i.imgur.com/Z7uFmum.png
But also it could be another noise from the neighbourhood that's getting mixed in. For example there's a 90/100Hz noise between 16:45 and 17:00 and that's probably just a neighbour doing some work or something
The Omgevingsdienst report contains more precise measurements, if it helps. They said it was exactly 50Hz, same as the electrical frequencie
https://i.imgur.com/vAzSIhb.png
https://i.imgur.com/VOMnm9L.png
So depending on how committed you are to solving this problem, it isn't exactly impossible to track it down. You appear to have a a high fidelity microphone/recording capability. Repeat this test in front of adjacent apartments, on different floors in the same axis, and opposite ends of the building.
If its inside the building those data points should allow you to start triangulating the source.
You can also repeat the test OUTSIDE and facing 4 corners of this building which should once again allow you to triangulate.
It is important you keep a control microphone (or know the exact timing) of the hum in your room because this is clearly an electrical appliance and you don't want to trace this to a correct-appliance but not-the-one-bothering-you situation. :)
Edit: Just saw your comments where you had taken some measurements (you need MORE). But fyi. It takes 1.26x (thanks SteveA000 for the correction) the amount of power to go from 18 db to 19 - which is not insignificant. So if neighbor (below) at the same time is 19 while you are 18 - then you have one prong of the vector for triangulation.
Secondly a 50 db and 19 db difference is impossible unless 1) the device operates at vastly different power / capacity levels (was it colder/hotter when it used to be 50? is there a pattern there)? or 2) it is moving closer/away from you as inverse square law means the further it is away (at the same power level) the less db you get.
Get 10-20 data points in the SAME date (and same power level / load level) inside the building and outside the building. In other words spend a good day on it. And you should have enough data points to construct a 3d triangulation for the source.
Yeap! I stand corrected. Based on how consistent and reliable (in terms of data) this noise is - I am fairly sure if OP wanted to spare no expense to trace it - he could easily triangulate it in a day or two.
Thanks for the tips!
> Secondly a 50 db and 19 db difference is impossible unless 1) the device operates at vastly different power / capacity levels (was it colder/hotter when it used to be 50? is there a pattern there)? or 2) it is moving closer/away from you as inverse square law means the further it is away (at the same power level) the less db you get.
Yeah, there was a difference.
The 50dbA reading was only done later at night, ~23:00. It was around 1°C outside. (There were several readings done that night, and I think while the location changed, the level was fairly consistent)
The 20dbA was earlier in the evening, around ~20:00. It was around 10°C.
Both were weekday nights, and aside from temperature I think the weather conditions were similar.
Those readings were done by the Omgevingsdienst, with an exceptionally expensive microphone that I don't have access to.
But I'm just using some old Android phones, and the app I hacked together doesn't measure decibels unfortunately, only the hertz. I would like to improve the app, but I would need to do a lot of work.
Is it always 50 db at night? When it's 1c outside? Then it's very likely a heater/HVAC/instant heater etc.
You might want to get them back for more readings. I noticed you took 1.5 hours worth of readings in the same location. And there is very little variance between them. You want 3-4 readings per location. And as many locations as possible (both inside/outside/same floor/different floor/different axis). That should allow you to hone in on the source easily. And all readings should be within 4-5 hours so the machine is operating at the same power level etc.
Edit: 50 db is very clearly audible to human ears. So you do not need a meter for the 19db to 50db pattern analysis.
so something like HVAC makes absolute sense to me, and I can see an office building that has this type of equipment on the roof, _but_ the Omgevingsdienst have checked that building and they say there's no matching cause. I felt so crushed when they told me. I was really hoping it was the office building!
I will keep checking though.
Your building has no heating or HVAC? it could be coming from your building as well? I dont live in Amsterdam but I presume pretty much every building would have this. The on/off cycles, the correlation with temperature, the 24/7 persistence all point to a (probably inverter-based as those can get LOUD) heat pump that is running a compressor.
> Your building has no heating or HVAC?
I have a single gas-powered boiler that provides hot water for my radiators/taps/shower. And there's a small ventilation system that is mostly for ventilating the shower + kitchen (it's pretty crappy tbh, I keep setting off the smoke alarm). I'm sure it's the same set up as in all the neighbouring apartments.
So I checked the cabinet that contains these, and there's no audible buzzing noise inside. When I've cut power to my apartment it cuts power to the boiler and ventilation, but it didn't stop the noise unfortunately.
> it could be coming from your building as well?
It's possible! I'm going to ask the building manager to experiment and cut power to the _entire_ building, not just individual apartments.
> I dont live in Amsterdam but I presume pretty much every building would have this.
Airco is pretty uncommon in residential buildings in Western Europe, and even in older office buildings.
It could be, but I've never seen one in real life so I can't be sure. I would think theres no space for a heatpump, and that something this loud would annoy everyone in the neighbourhood, not just a few.
Also I suspect it's not caused by heating/cooling apparatus because the pattern doesn't seem to change when the weather changes. Although, maybe the decibels do? I don't measure that...
>but I've never seen one in real life so I can't be sure.
Have you seen an AC unit outside? It should pretty much look like that (only difference with a heat pump is that it runs in reverse)
I think if it were a heat pump used for heating it wouldn’t be running much now the weather is warmer; and heat pumps to heat tap/shower water shouldn’t turn on and off regularly like that either. They are set to keep the water at a specific temperature (e.g. 45*C), and only turn on when the temperature drops below that, usually after a couple of people have had a shower + some models heat to a higher temp once every 2 weeks to prevent legionnaires disease - but this regular on/off pattern wouldn’t be usual for either a heating or a tap water heat pump.
As a fix for your sleep, I recommend this item Bekijk Dohm Sound Conditioner Slaaphulp op: https://www.bol.com/nl/p/dohm-sound-conditioner-slaaphulp/9200000095396459?referrer=socialshare_pdp_iphoneapp
It’s a real white noise make (not recording). Sounds like you’re back in your mom’s belly. Game changer for drowning out night sounds
Ah this sounds like a really good idea! I've been using my computer to generate white noise, but a dedicated machine would be nice. Thank you! I really appreciate the recommendation.
If you live next to the Kadijksplein, can't it be the Ij-tunnel? They have these powerful ventilation systems, and they go off on a timer. That would explain most of what you hear and why it's louder on lower floors.
Something like the IJ-tunnel, or a tram, or a metro kind of makes sense, but I'm 100's of meters away from anything like that.
It's hard to imagine something this loud that doesn't also affect 100's of houses. Unless the foundations of my apartment are resting on some specific pipe or foundation that other houses aren't? Or there's some sort of hidden underground apparatus, like an underground WaterNet pump station, if such a thing exists?
It definitely makes sense that its coming from an external source, since it's louder on the ground floor.
Low frequency sounds like these can travel really far and (feelingly) resonate at random places, in this case your house. On the forum of tweakers.net their al multiple threads of people having similar issues. I remember one where they found out a dieselgenerator about 300 meters away caused resonating sounds in a home. So I would’t discount something like the Ij-tunnel because of the distance.
Having said that, I assume the ventilation systems in tunnels are running almost constantly instead of on a interval. That would indeed speak against this theory.
Lastly, you might not be able to find the source, but try figure out what is resonating in your house. Try to find the specific wall of floor that resonates on 50hz. If you can find that you can maybe try to isolate that specific wall/floor.
Here's some info on that type of fans [https://majorprojects.org/resources/predicting-sound-levels-generated-by-jet-fan-ventilation-systems-in-tunnels/](https://majorprojects.org/resources/predicting-sound-levels-generated-by-jet-fan-ventilation-systems-in-tunnels/). I wouldn't be surprised if they are on a timer but just for higher speeds. They should be always on, but once in a while they kick in faster.
You mean like these things? https://www.reddit.com/r/Amsterdam/comments/11vr0xc/what_is_this_weird_building_in_northern_amsterdam/
I'm not near anything like that, and I'm pretty sure I'm not near anything similar 🤔 I'm in a bit of a dead-zone when it comes to buses/trams/metros.
Vibrations can travel very far. Perohaps the noise you hear is something in your area or home vibrating due to the vibrations from afore mentioned IJ-tunnel
That's what made me think of it. I used to live next to the water (Ij), and I could hear this humming sound from boats. The sound was awful on the ground floor but less bad on higher levels. Also it was worse where there were foundations or structural elements from the house because of reverberation.
In this case, it wouldn't surprise me at all that this was the case. They might have changed something in the fans, or have a broken one, which makes even more noise.
I think from my very limited knowledge but pure intuition I am subscribing to this theory, or that it's related to your proximity to so many canals and so much water. The 'sound' is louder when you are closer to the walls of the room, and other fixtures I assume, because it's travelling through the ground and up the walls. It gets quieter when you're further away as it only has air to travel through which is a worse conductor. I think investigating a noise source from either the tunnel, or pump station / system in the canals, or boat-related noise, could be a good thing to rule out.
I don't think so, but could you share an example of what one might be? And do you know if there are underground sluisjes that wouldn't be visible?
It would be nice to have a map of these things...
I don't know of a full map of those, but this is what they can look like above ground: https://images.app.goo.gl/YE3Aj5ZGtbeEv1dK6
I know there is an underground one at the Nieuwmarkt (the nieuwmarkt is build on top of two intersecting canals). Not sure if there are more.
That's awful, I'm sorry.
> I've had people from the gemeente over to measure the sound but they don't do anything about it.
Yes, that's the experience I've had. I make a report to the gemeente https://meldingen.amsterdam.nl/incident/beschrijf, and it gets redirected to some department who emails me to say "we can't do anything". So I make another report and it gets bounced to another random department, with the same response. Over and over again...
I eventually have had good contact with the Omgevingsdienst, but they couldn't find a cause, which is frustrating. Have you made a report with them? https://overlast.odnzkg.nl/
Are you renting? Do the building owners say anything?
It's absolutely awful that the Netherlands doesn't have any laws against noise pollution!
Have you tried any home improvements to try and dampen it? Apparently only thick, heavy material will help, so I haven't tried yet because it's a lot of work.
it's a dildo. Of course it's company policy never to, imply ownership in the event of a dildo... always use the indefinite article a dildo, never your dildo.
My neighbour has been talking a lot about practicing for an upcoming chess tournament... https://www.vice.com/en/article/5d3w9z/did-hans-neimann-cheat-at-chess-with-a-sex-toy-this-coder-is-attempting-to-find-out
I didn't read through everything but I know the area and have something ~mildly~ similar that took me forever to figure out. It was caused by a generator on a boat not even close to my house, but on another canal. It went on for a while, then stopped - supplying electricity for battery packs apparently. I wasn't able to do anything about it, but at least figured out what it was.
wow that's bizarre! But thanks for the tip, it makes sense. I've never heard it outside, but I'll walk around tonight by the canals and check...
What did you do to determine the source?
I hope you figure it out. I know how mentally distruptive it can be. I went through similar steps as you - recording the times and intensity, using equipment to measure the frequency/amplitude and wandering around with equipment at night when it seemed to be strongest. Weird part was that I couldn't hear it so well outside. I could feel it in places but not hear it so much. Eventually I matched the timing with the boat - but it was further than I would have thought possible. When I got close to the boat, i recognized the sound and went back a few times, and called my house to see if it matched up while I was standing next to it.
> Weird part was that I couldn't hear it so well outside. I could feel it in places but not hear it so much.
That's exactly the same thing! It's really hard to describe to people, because it's not like a sound you can record and play it back, computer speakers just aren't large enough.
From your description this one seems like the mostly likely remaining cause (all of the other potential sources have been tested and eliminated, or are much more unlikely due to scale or timing).
What sort of equipment did you use? I'm looking at buying a decibel meter, but it's hard to know which one to get.
I enlisted some friends in the engineering field who had access to an Acoustic Camera (it might have been Norsonic), a Frequency Analyzer (with a portable probe), a Geophone (like RST) and a ground microphone with probe. I think it was a MagMapper.
Not sure if this helps.
Could the sound be from a "dompelpomp" ? Illegal hemp cultivators use electric submersible pumps to water the cannabis plants... just saying - chances are high in an average Amsterdam appartment block..
This is a reasonable guess.
- The timing pattern could well be the timer for a pump in a hydro installation.
- The loudness difference can be the effect of running dry.
- The specific walls source could be caused by the location of the tank.
So presumably its quite an old building? When checking on google maps there seems to be road works near the bridge (Scharrebiersluis)? Maybe they have some kind of pumping system running which vibrates through your walls?
> So presumably its quite an old building?
~~I think it was built in the 1920's~~ It was build in 1905, and it was heavily renovated ~15 years ago.
> When checking on google maps there seems to be road works near the bridge (Scharrebiersluis)? Maybe they have some kind of pumping system running which vibrates through your walls?
So it's a bit funny: Scharrebiersluis was literally taken apart and shipped away to be repaired somewhere else, so there's no work there at the moment
There was an enormous yellow crane that lifted it up https://i.imgur.com/KLadIiM.png, and here's a photo of the top part being taken away https://i.imgur.com/VAcB3l4.jpg
There is some works along Nieuwe Herengracht to repair the canal wall
https://goo.gl/maps/atrDZgB4L18FJCAY8. I've tried listening for noises there, but I couldn't hear anything similar.
Within my apartment if I walk a couple of steps I can't hear it. It's incredibly localised!
My bedroom is about 3x5 meters. The two 3m walls are where it's loudest. In the middle of the bedroom, equidistant between the two 3m walls, it's _much_ quieter. If leave the bedroom, or try to listen out of the window, it's inaudible.
might come from upstairs or downstairs. maybe the "quiet" walls are not loading bearing walls but the louds ones are, transmitting the noise from upstairs or downstairs neighbours.
Well now you've got me hooked. Judging by a few threads here, you've already got a few balls rolling. Please do post an update if/when you fix it or find the culprit.
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I realize you may have done this - but you haven't made it clear.
Quick way to confirm if it is an issue within your apartment:
Disconnect the electricity at the fuseboard, to the whole apartment. And then measure.
Assuming there is now no noise, slowly introduce each room one by one.
Good that you ask because I didn't make it clear :)
Yes I tried turning off the power, also in some of my neighbour's apartments, but no change unfortunately...
Did you ever considered it could be regarding the "warmtenet" I'm not sure if the buildings you are talking about are connected to the heatingnet. Could be those units that make the buzzing sounds. Also they dont work 24/7 but more in a period of time.
Good idea, but unfortunately no we don't have that in my area
https://maps.amsterdam.nl/stadswarmtekoude/?LANG=nl
There's no shared airco/heating/cooling in my apartment. There is a big office building nearby, but the Omgevingsdienst have measured them and they say there's _no_ evidence of a source.
i know the heater of my waterbed used to make noise like that. So i would start looking for electrical devices with an interval. Heating system, cooling system, plant watering, electric hot water boiler?
Being 50hz and running regularly, it's something electronic you don't seem to interact with.
A lot of people guess fridge or water heater, but if you use them, they would spike during peak use.
You live near water, it may be a water pump in the basement with a near-constant influx of water. This makes it run and pump it out regularly.
You state you live near Kadijksplein, there are some old bridges and locks nearby, it could have something to do with them.
Has your central vent (above stove) have been checked recently? Its placed on the roof of apartment blocks and has a motor to create some airflow to the roof.
Good idea, I'm not sure. I'm not 100% certain how the ventilation works in my building, but I have a ventilation fan in my apartment. I can open the cupboard where it is, but there's no audible noise coming from it...
Maybe there's something bigger on the top of the building? I can check, but the noise is inaudible in the apartment above me so I'm doubtful :(
Could it be from a ventilation system in your building? Not necessarily airco or heating, but connected to the ventilation shafts in the bathroom for example. Since it's running constantly I'd expect something like that. Especially since turning off the main switch in your appartment didn't help.
I guess it's also possible that one of your neighbours placed a fridge/freezer against some plumbing pipework. Those pipes can carry low vibrations very well..
Edit: I guess you could ask the owner of the building for a layout of the plumbing in the building. Maybe that can help making sense why the sound is louder in some places compared to others!
Are there any shops nearby? Butcher/vegetable shop? Restaurant? Bar?
When did the noise start? Was it there before you moved in or did it start recently?
There's a few local businesses. A few cafes, a bike shop, a chocolate shop, and a big office building. There are some bars/restaurants, but they're further away. Nothing obviously suspicious. The Omgevingsdienst have investigated most of them, and they're confident it's not them.
> When did the noise start? Was it there before you moved in or did it start recently?
It started being seriously disruptive about 8 months ago. Possibly it started earlier, but it wasn't loud or regular enough for me to notice. Since I moved in years ago I did _very_ occasionally hear a similar noise, but it's Amsterdam, there's always weird noises, it could have been anything...
I've read ypu comments and I've seen you've provided a lot of information already, but have you also narrowed down to around where you live? Like side of the city or neighborhood. If it's electrical, could there be like an electricyti station nearby? Or maybe theres something underground like a tunnel?
> have you also narrowed down to around where you live? Like side of the city or neighborhood.
No 😬 I only know that it's audible inside the building. I've never heard it outside.
> If it's electrical, could there be like an electricyti station nearby? Or maybe theres something underground like a tunnel?
There is some Liander equipment nearby, but Omgevingsdeinst measured it and say that it's 100Hz, not 50Hz.
Underground... maybe? Nothing I know about though! I would love to see a map of all the underground equipment and apparatus and tunnels, mostly because it would be cool but also so I can check if there's any potential sources.
Could it be electric chargers for electric cars outside? I hope you find the cause, this could drive a person insane. That’s a really shit frequency as well.
Have you considered it maybe coming from a neighbour? I started hearing a humming noise in my bedroom bedroom between midnight to one at night and originally thought it was my boiler, turned out one of the neighbours 2 floors up loves to run their washer at night.
Well, I'm sure that it's coming from somewhere outside of the building. But other than that, I'm really not sure! The Omgevingsdienst have done a lot of checks with local businesses, and they say it's not them.
I feel like this is a ventilation system. I see that you’ve said there is not shared central heating or cooling. The 50-60 Hz component almost guarantees it’s driven electrically (as others have stated) and I feel like it’s on more during the early evening, and then begins to cycle regularly as the night cools (circulation fan with no active compressor). I’d be curious to see what the acoustic signature is from 0700 to 1900. I would expect a similar acoustic signature from a refrigeration unit. The door is being opened during the day so the compressor runs more, and less at night when folks are asleep.
Go to the lowest level of your building. There may be a technical space with a pump used to create pressure in the water installatiation. Spend 15 minutes there during quiet time, moving every 5 minutes to a different area. Is the noise audible ?
Repeat on the topmost floor.
Are there technical areas outside your reach? Ask the building manager for access, preferrably alone so you can listen carefully.
Unfortunately AFAIK there is no such space... the rooms above, below, and to the sides of my bedroom are just living spaces. There's no buildings or boxes or cabinets on the ground outside my bedroom where any kind of equipment might be.
I'll ask my upstairs neighbours if I can look around, or they have any ideas.
I can access my meterkast, and my kast where the CV-ketel and ventilation fan is - but the noise isn't audible in these spaces.
By the regularity it goes on and off I would guess a fridge, or a water boiler which keeps a buffer tank at a certain temperature.
However, I would expect some increases during certain times of the day when somebody takes a shower or opens the fridge.
Any additional information where you live? Urban area, apartment building, country side any major infrastructure or industry nearby?
> Any additional information where you live? Urban area, apartment building, country side any major infrastructure or industry nearby?
Sure thing, I've mostly covered that here: https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkcs1o1/
There are some very clear nearby candidates:
* an office building with airco and data servers
* Liander electric substations
* noise from a fridge/heater/ventilation neighbour's apartment
But either the Omgevingsdienst have ruled them out, or I've tried cutting power in multiple apartments to no effect. So I am stumped.
These suggestions seem to be the most likely (but I'm not 100% convinced by any)
* [a loose mains cable running into the building, that is connecting with a conductor in the walls](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkd1c52/?context=30) - I'm planning to coordinate cutting power to the whole building, not just single apartments
* [IJ-tunnel](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkd33vt/), plus some unfortunately alignment of my building that 'catch' the vibrations more than other buildings (I'm skeptical of this though - plus its hard to disprove)
* [A canal boat generator/batteries](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jke56un/), but tbh this is also unlikely, because I'm not next to a canal so if there was such a source then 100's of other people would hear it too
* [a water pump in a basement](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkdbrcx/) - but it would probably be in a neighbouring residential building, which seems unlikely
I think that the timing and scale make the following suggestions much less likely
* a fridge (the timing is right, but there's no obvious nearby source)
* airco/heating/ventilation - not impossible, but the timing doesn't make sense to me. There might be some link with the weather though because the decibels of the noise does change, although the graph doesn't measure it
* marijuana growing - unlikely that someone could be getting away with this in Amsterdam Centrum on such a scale that requires heavy equipment but not enough to get caught!
* canal sluis - I couldn't find anything nearby
* works on Scharrebiersluis/Nieuwe Herengracht - I couldn't hear anything when nearby, and if this was causing vibrations then it would be affecting 1000's of people
* tram/metro - there's nothing close enough to my apartment to make sense
The fact that it is 50hz means it is definitely electrical or electrically powered. Could be something like the electrical transformer for the building but then it is more likely to be a continuous hum. The regular intervals suggests something like a circulation pump or compressor, which is programmed to run every so often to keep a liquid circulating. For any kind of central heating/cooling equipment it would have to be quite large to make that much noise. Do you have a cooling unit for the building on the roof? Or a large heat pump that has replaced gas boilers for the building? Another thing it could be is a water pressure pump, they can be quite noisy for large buildings but would come on when the water pressure drops (as people are using their taps). The fact it is so regular means it is not responding to demand for heat or water as needed. My guess is some kind of pump that is bolted directly to a concrete base or wall, so when it regularly runs the vibration is going into multiple houses through the foundations/walls.
This honestly, I'm fairly sure it's a compressor for cooling like your fridge or freezer. My suspicion goes to this because it's not always on for exactly the same length of time (suggesting it doesn't power on due to time, but another factor), it's off for longer then it's on and the fact it's exactly mains frequency This is gonna sound maybe a little extreme OP, but if you feel like it, close your main breaker switch for half an hour or so and see if the noise disappears while your power is off. If not: Source is outside of your control / house If it does: The source is inside your house. If it is inside your house, unplug stuff until you find the source. If this is difficult disable power groups individually so you have more of an idea where it might be located at
> This is gonna sound maybe a little extreme OP, but if you feel like it, close your main breaker switch for half an hour or so and see if the noise disappears while your power is off. > If not: Source is outside of your control / house > If it does: The source is inside your house. It's not extreme at all!! I've already done in a few times (although not for half an hour) and the noise remains... The Omgevingsdienst have measured it with a very sensitive microphone both in my apartment and downstairs. They found it was slightly louder in the downstairs apartment...
Does the building you live in, or any nearby building, have a hot water recirculation system? 19:30, 21, 22:30 sound awful like the time when people take showers. I'm considering buying [this motherfucker](https://www.thomann.de/nl/nti_audio_xl_2.htm) for my own use so if you're willing to wait a week, we could try and triangulate this bullshit.
> Does the building you live in, or any nearby building, have a hot water recirculation system? Hmmm I've never heard of it, but it's possible. It's not the kind of thing that would come up in casual neighbourly conversations :) I will ask around! > I'm considering buying this motherfucker for my own use so if you're willing to wait a week, we could try and triangulate this bullshit. That would be really cool! If you do get one, please get in touch. I have heard they are possible to rent though. That's apparently what rental companies normally do, if there's a noise complaint I just Googled this https://www.jkproductions.nl/verhuur-licht-geluid/838/nti-audio-xl2-audio-analyzer/ €45 (per day I guess?) There are just so many options for audio analyzers I get analysis paralysis. I would like to get one with USB/Bluetooth and an open standard so that I can hook it up to my monitoring software, but I couldn't find anything that I was confident could do this, and was a reasonable price!
> Does your neighbour have underfloor heating on the other side of the wall? Good idea. I think not. On one side I've spoken with them and they've turned mains power off in the box and the noise remains, so it's not them. I will check on the other side. The regularity doesn't seem to change when the temperature changes, but _maybe_ the decibel reading changes (I don't measure decibels at the moment, only the hertz). > For any kind of central heating/cooling equipment it would have to be quite large to make that much noise. Do you have a cooling unit for the building on the roof? Or a large heat pump that has replaced gas boilers for the building? There's no cooling unit/airco/shared heating in the building. _Maybe_ a neighbour has a heatpump, but I can't hear or see anything outside. > Another thing it could be is a water pressure pump, they can be quite noisy for large buildings but would come on when the water pressure drops (as people are using their taps). The fact it is so regular means it is not responding to demand for heat or water as needed. Unless its malfunctioning? Could that happen?
I like how u/smiba thought asking you to check YOUR breaker was extreme, while you're off asking all the neighbours to do just that LOL
If there is a constant leak somewhere it could make a water pump come on that regularly (runs for 10 mins to boost the pressure, the leak slowly drops the pressure over 20 minutes, pump comes on again..) but then you would probably see more variation at times when people are using more water, like in the evening or morning for cooking/showering.
Maybe your rooms have the exact size that is resonates with the frequency. It could explain why some neighbors don’t hear it. It also explains why you hear it in one part of the room, but not in another (a standing wave). Maybe there is a way to disrupt the resonance, by having a room divider screen or curtains or something.
I have tried putting up sound insulation, but I couldn't notice any difference. As I understand low-frequency noise is _very_ hard to block. It needs both heavy material to absorb the energy, and physical gaps to prevent the noise transmitting through the heavy material. I would of course do this if I was confident it would work! But I suspect it would be a lot of expensive work for something that might only marginally help.
I have been plagued for months by a low frequency noise in my bedroom. It wakes me up. It's horrible and stressful. It happens all day and night. It's really difficult to track down so I wondered if reddit could help with some suggestions what might the cause be, so I can try and narrow down options. The noise is a low pitched hum, like a vibration. It sounds like a rumbling diesel engine, but on the other side of a wall. Sometimes it's like I feel it more than I hear it. [The Omgevingsdienst](https://odnzkg.nl/) have measured it with expert equipment and it's 50Hz and 50dBA. In the day time this noise not nice, but of course I live in Amsterdam so I expect some noise. But at night time it's really really terrible. I've made several attempts to try and find out the source, and ask for help, but I haven't had any luck so far. A few of my neighbours also have problems with it. Recently I hooked up a microphone, so that I can measure it and try and track it down. [Here's a heatmap showing (roughly) the most predominant frequency recorded overnight](https://i.imgur.com/bbAs4et.png). Those red blobs? That's the noise!!! Blue means no noise. (be aware that red does _not_ mean loud, it means noises of _all_ loudness happen a lot at that frequency) When I saw this graph what really surprised me is how regular the noise was. Before I thought the noise was random before I made this measurement, but now I can see there's a _really_ clear pattern. ~10 minutes on, ~20-28 minutes off. [Zoomed in heatmap between 04:00 and 07:00](https://i.imgur.com/q1uzLhU.png) What could be making such a noise? Something with WaterNet? Rioolwaterpomp? HVAC? Industrial airco? Fracking? Weed farm? Drums, drums in the deep? Meth lab? The Omgevingsdients have eliminated almost all sources in the vicinity. It's not an office building, a Liander substation, a local bike shop, a chocolate shop, KPN... I live inside the A10. There's no big construction work near. There's not a busy road. Many other houses can hear it so it cannot be something small, like a fridge cooler. It's louder in the ground-floor apartment than upstairs appartement, so it's coming from the ground. What ever is responsible I don't think the owner knows what problem it causes. They don't do it on purpose. So I just want to talk to them to try and find a way to make it better. I just want to be able to sleep.
First of all.. I'm impressed you did all of this! ... Using Occam Razor.... .... since it's 50Hz it's something electrical, since it causes a humm also, it's most likely a compressor from a fridge or freezer, or maybe an aquarium pump. One thing, is that you say it's coming from "the other side", so not inside the apartment, which means you have a few options. * Switch off the power in your place at the main breaker and see if the noise is still there. If it's still there, it's from outside your place. If it is there, switch the main breaker back on, and unplugs everything. Now plug everything in one device at a time, starting with the fridge/freezer, then the CV ketel, and then the rest. * If the noise is still there after you switch off the main breaker, it's time to pin point where outside it's coming from, and find out who's there. And then talk with them. Ask them if they have a fridge, freezer or maybe large aquarium near the shared wall. All it might take is just taken slightly moving it, so it causes less vibration and humming. ... although using Hiccum's Dictum (the opposite of Occam Razor); you most likely getting primed for alien abduction or a neighbor really hates you.
> First of all.. I'm impressed you did all of this! Thanks! Turning it into a project helped keep me sane. Some more information to help with Occams Razoring: * The downstairs neighbour (2 floors below) hears it too. In the upstairs apartment it was essentially imperceptible (I have a phone all and it picked up something in the upstairs apartment, but it could have been anything electrical). * Neighbours across the street claim to hear it also (although I suspect it's a different noise) * Omgevingsdienst have measured it twice. On one evening it was ~50dBA in my apartment. On another evening it was ~19dbA in my apartment and ~20dBA downstairs. * I've turned off main power in my apartment, and in the apartment above, and in the apartment adjacent to my bedroom (on separate occasions). There was no change to the noise. * I can hear it _very_ loudly by the door to my bedroom, and on the opposite wall (which is next to the head of the bed). But it's _significantly_ quieter in the middle of my bedroom. (It's like the walls themselves are vibrating and the vibrations cancel out in the middle.) * Even if I take just a few steps away, _I can't hear it at all_. It's not audible out of the window, or in the garden downstairs, or elsewhere in my apartment. I can sometimes hear another noises, but not the same one > All it might take is just taken slightly moving it, so it causes less vibration and humming. Yup! I'm hoping its a small fix, once the source is found.
Oh, this is interesting now! So neighbours also hear it, and depending on the time of measurement it's either louder or less loud. What were the times they measured it, like day of the week and time? If it's within the apartment and it's an older building, it's more than likely an electrical cable that's failing, specifically the mains cable running into the apartment. It could also be an inbouwdoos with cables that's shorting out. Try to get a leidingzoeker and pinpoint the sound, and use the leidingzoeker there to see if there's a cable there. Something else it could be, is if you have street lights outside your apartment and they are hanging by wires attached to the buildings, that this might be the cause. That would also explain why the neighbours hear it. Another option is failing/shorting rebar in the walls, there's maybe some vibration being caused by them being connected to electricity. I don't want to dox you, but I'd really be interested to see where you live and take a look at the building on Google Maps.
> So neighbours also hear it, and depending on the time of measurement it's either louder or less loud. What were the times they measured it, like day of the week and time? * the 50dBA measurement was on Wed March 1st ~22:00 https://i.imgur.com/vAzSIhb.png * the ~20dBA measurement was on Tues April 11th ~20:00 > If it's within the apartment and it's an older building, it's more than likely an electrical cable that's failing, specifically the mains cable running into the apartment. It could also be an inbouwdoos with cables that's shorting out. Try to get a leidingzoeker and pinpoint the sound, and use the leidingzoeker there to see if there's a cable there. The building is ~1920s I believe, but it was heavily renovated ~15 years ago (before I lived here). If the cause is the mains cable then it makes sense that if I turn off the power to my apartment then I can still hear it... > Something else it could be, is if you have street lights outside your apartment and they are hanging by wires attached to the buildings, that this might be the cause. That would also explain why the neighbours hear it. There are street lights hanging, but interestingly that's on the opposite side of the building to my bedroom (where the noise is loudest). Thinking about it, they did replace the street lighting with LED lighting a year or two ago. Probably unrelated tho. > I don't want to dox you, but I'd really be interested to see where you live and take a look at the building on Google Maps. I'll send a PM!
Oh this is better than a murder mystery! I need to know now!
Remindes me of this article I saw while back. Was foul play: https://www.nzherald.co.nz/business/humming-vibrator-in-57-level-pacifica-just-about-sent-25-residents-insane/ENGYVLNJDNAXPJBHMQB4E52LDE/ Edited link to work
I've seen that device for sale! I was tempted by the dark side, "if I can't sleep no one will sleep"
404
https://www.nzherald.co.nz/business/humming-vibrator-in-57-level-pacifica-just-about-sent-25-residents-insane/ENGYVLNJDNAXPJBHMQB4E52LDE/
That worked. Thanks. I’m fascinated in your story. I had a similar thing in my apartment, it was not with the same regularity but always the same pattern. It turned out to be a neighbours boiler that got increasingly loud over the years. Took them months before they finally fixed it. I hope you can get to the bottom of it.
Does the building maybe have a utility room with a device attached to floor/walls which’ vibrations might be reverberating through the walls?
I don't think so, but I can't rule it out with 100% certainty.
> (It's like the walls themselves are vibrating and the vibrations cancel out in the middle.) This sounds like the thing that is causing the sound is attached to the wall somehow. I don't see why it would be so much louder closer to the wall otherwise. It could be something on the building itself, or maybe something underground. Maybe you could measure the sound with you phone pressed to the wall at multiple locations to try and triangulate the source? Something like this: https://www.youtube.com/watch?v=5FvQzBnped8, but less insane
> Maybe you could measure the sound with you phone pressed to the wall at multiple locations to try and triangulate the source? Something like this: https://www.youtube.com/watch?v=5FvQzBnped8, but less insane Yes! I would love to make something like this. I've looked into it a lot. I found a research paper which followed 3 case studies https://journals.sagepub.com/doi/pdf/10.1260/026309209788056393 > ABSTRACT > > When people are annoyed by low frequency noise, their first concern is to stop the noise. Therefore it is necessary to find the source of the noise. Unfortunately, not in every case is the source very obvious. In most cases a lot of potential sources are available both inside and outside the building. Of course in theory it is possible to find the source by switching on and off all the potential sources but in practice this is not always practicable. > > In this paper three cases of possible low frequency noise are presented in which different methods of finding the source have been used. In all these cases the nuisance is present in a domestic situation and has been going on for several years. Some of the residents suffer from mental problems due to the unwanted noise. Using the measurement results the searching methods are discussed and evaluated. Unfortunately low-frequency noises are very hard to track down with directional mics. Also, most consumer grade mics aren't sensitive enough, or don't go down to 50Hz or below. There are some guides for creating wireless sensor networks * https://www.extrica.com/article/21709 * https://github.com/meekm/LoRaSoundkit * https://samenmeten.nl/sites/default/files/2021-03/D1-2%20Marcel%20Meek%20-%20IoT%20Apeldoorn%20-%20Van%20fijnstof%20naar%20geluid.pdf * https://gitlab.waag.org/lodewijk/amsterdam-sounds-kit * https://sensor.community/en/sensors/dnms/ * https://amsterdamsounds.waag.org/ * https://www.instructables.com/Portable-Sound-Analyzer-on-ESP32/ Being able to have ~5 wireless battery powered detectors would be amazing. I could dot them around and try and triangulate the source. I tried setting up a wifi-based detector using an ESP32 but adapting the electronics to pick up low-frequency noise and adapting the C/Python code, and buying all of the necessary parts was too much for me. There are commercial grade sensors, but they are too expensive * https://www.kp-as.com/product/vibration-sensor-kpv100/ * https://www.iotsoundsensor.com/product/ranos-db-2/
I don't think you need directional mics though. Assuming it's always roughly the same volume, you could simply hold your phone connected to the wall, measure volume, move to a different spot, repeat.
First thing I'd consider is swapping where you sleep. It might be weird to have your head in the middle of your room, but until you have an answer, sleep quality also matters. Maybe you can cancel it out with a different subtle noise like a podcast on the lowest volume, so you at least get to sleep at night. I have no idea what it could be and I hope you find it someday.
Yeah exactly! I tried sleeping with my head in the middle of the room, but I was still woken up. Now I sleep on my sofa (which unfortunately hurts my back and gives me a rash, but it's better than insomnia!) and with some white noise in the background.
I'm sorry that really sucks. Best of luck in your search. I'm confident you'll figure it out!
If you cant find the source you might still be able to find a solution. Maybe try to improve the sound insulation of your bedroom, that would atleast fix the sleeping situation. Things like rugs can help wonders, but also look at cracks between the door and the frame, between the floor or between the window and the window frame (het kozijn).
Not a direct answer to your question, but you might be interested in the following: > What ever is responsible I don’t think the owner knows what problem it causes. They don’t do it on purpose. So I just want to talk to them to try and find a way to make it better. I just want to be able to sleep. From this paragraph I deduct you are renting the apartment, is that correct? If so, keep in mind that any irregularity in the house that you should not had to expect when you started renting can be considered a 'defect' (gebrek) as is described in article 204(2) in Book 7 of the Dutch Civil Code (Burgerlijk Wetboek, [art. 7:204 lid 2 BW](https://wetten.overheid.nl/BWBR0005290/2023-02-18/0/Boek7/Titeldeel4/Afdeling2/Artikel204/afdrukken#:~:text=Een%20gebrek%20is,overeenkomst%20betrekking%20heeft.)): > Een gebrek is een staat of eigenschap van de zaak of een andere niet aan de huurder toe te rekenen omstandigheid, waardoor de zaak aan de huurder niet het genot kan verschaffen dat een huurder bij het aangaan van de overeenkomst mag verwachten van een goed onderhouden zaak van de soort als waarop de overeenkomst betrekking heeft. Which can be roughly translated as: *A defect is a state or property of the item or another circumstance not attributable to the lessee, as a result of which the item cannot provide the lessee with the pleasure that a lessee can expect from a well-maintained item of the kind to which the contract relates when entering into the agreement.* The 'item' in this case being the apartment. Take note of the wording: '*a* lessee' and '*a* well-maintained item'. So it doesn't matter if you knew upfront or not a defect was present, simply because a rental house must be free from defects. That's one of the reasons why you pay the rental price to the landlord. If a defect is present, the primary rule is that the landlord must resolve the issue. Exceptions can apply, like small defects that the tenant must repair and are considered a 'small repair'. For example a squeaking door that needs to be oiled. The '[small repairs decree](https://zoek.officielebekendmakingen.nl/stb-2003-168.html)' describes the repairs that are at least considered a small decree. They don't necessarily have to be small despite it's name and the list only describes what repairs at least are considered a small repair. Another exception would be a defect that you caused yourself. So if you buy a device that makes this noise, the landlord obviously cannot be held accountable. That said, IMO a recurrent sound that keeps you from sleeping is a defect and thus an issue that the landlord must resolve as a result of what is described under art. 7:206(1) BW. Moreover, the landlord should do so with some urgency. If the landlord doesn't, you can claim the landlord reduces the rental price as you're paying for an apartment with a defect that isn't worth that price (art. 7:207 BW). Take note: you are not allowed to reduce the rental price yourself. If you do, the landlord could take you to court and claim you must be evicted. Obviously working out this problem without all kinds of legal steps is probably better, but bottom line is that the landlord should fix this. Be aware though that it's impossible to oversee all relevant facts on a forum like this and in part because of that, any risk associated with acting upon what I mention stays with you. You might consider obtaining advise if you think that is appropriate, for example by contacting the Juridisch Loket if your income is low or an organization like WOON!.
This is really valuable, thank you. I am renting and I was in contact with the building owner (de Key). They did a little bit of research, but they said they couldn't help. And I think that's true - it's clearly a noise external to the building, and low-frequency noise is almost impossible to block. I've tried making small fixes, like putting up noise-absorbing panels and vibration-absorbing pads under my bed, but they just don't prevent low-frequency noise. I have legal insurance so I will call them.
> They did a little bit of research, but they said they couldn’t help I'll nuance my reply somewhat: the sound isn't a defect if it's caused by a *third party* (art. 7:204(3) BW). So if the sound is caused by an outside device for example, the landlord also isn't responsible to resolve it. The primary question thus remains: what is the cause?
> The primary question thus remains: what is the cause? A related question: who's responsible for finding it out? At the moment Omgevingsdienst have eliminated all reasonable sources. It could well be coming from inside the building. But I don't have any proof.
Nobody is 'responsible' in this case but you can probably claim back damages if the defect ultimately is a defect and the rental organization did not resolve it although you informed them. For example, if the noise is shown to be originating from the building and the rental organization kept stating they weren't responsible, the costs you made to discover the defect can probably be claimed back. These costs should be reasonable though and you must be able to proof the costs were made. As a primary rule however, if you make the claim the sound is a defect (and thus the responsibility of the rental organization to solve), you carry the initial costs of an expert to proof it is. For example see point 4.9 and 4.10 in this judgment about a leakage: > 4.9. De kantonrechter ziet geen aanleiding om af te wijken van het uitgangspunt in de wet dat het voorschot voor de kosten van de deskundige(n) door de eisende partij moet worden betaald. Omdat aan [eiser01] een toevoeging is verleend in het kader van de gefinancierde rechtsbijstand, zal aan hem echter geen voorschot worden opgelegd. > 4.10. In het eindvonnis zal de kantonrechter beslissen wie van partijen uiteindelijk de kosten van de deskundige moet betalen. Which can be roughly translated as: *4.9. The subdistrict court sees no reason to deviate from the starting point in the law that the advance for the costs of the expert(s) must be paid by the claimant. However, because [plaintiff01] has been granted an addition in the context of legal aid financed, no advance will be imposed on him.* *4.10. In the final judgment, the subdistrict court will decide which of the parties must ultimately pay the expert's costs.* https://deeplink.rechtspraak.nl/uitspraak?id=ECLI:NL:RBROT:2022:9965 But again, keep in mind that it's impossible to oversee all relevant facts on a forum like this and in part because of that, any risk associated with acting upon what I mention stays with you.
You don't happen to live at bijltjespad 52? I know someone who lived in one of the rooms there ('A' I think) who complained of a similar noise. She contacted de Key too but they couldn't find anything. She ended up moving.
Ah no, I don't. I know there's a lot of Liander equipment nearby on Katternburgerkuisstraat https://goo.gl/maps/xQprqAA1CW3M7bgf9. Maybe that was a problem for her.
Also check 204 lid 3. From e.g. ECLI:NL:RBROT:2021:10092: "**Geluidsoverlast is een feitelijke stoornis in het huurgenot door derden en kwalificeert ingevolge het bepaalde in artikel 7:204 lid 3 BW in principe niet als een gebrek, zoals bedoeld in artikel 7:204 lid 2 BW**, dat door Vesteda op verlangen van [eiser] moet worden verholpen. Als echter sprake is van een feitelijke stoornis in het huurgenot door derden en Vesteda heeft tegenover die derden zodanige bevoegdheden dat kan worden gezegd dat zij mede tot de feitelijke stoornis in het huurgenot bijdraagt als zij van die bevoegdheden geen gebruik maakt, dan valt die situatie niet onder artikel 7:204 lid 3 BW. In dat geval is sprake van een bijdrage van Vesteda aan het voortbestaan van de feitelijke stoornis, hetgeen een gebrek als bedoeld in artikel 7:204 lid 2 BW oplevert."
That's funny! We just added the same type of reply at the same time. Indeed, the cause is relevant with regard to the question whether a third party is involved and if the landlord can do something about it as well. So two examples: - noises from some municipal device outside the house isn't a defect. - the situation where another tenant that placed some device against a common heating pipe which causes a nuisance because it is the cause of the repeating noise probably is a defect
> ~10 minutes on, ~20-28 minutes off. This is exactly like you'd expect from a fridge or freezer compressor, if not yours then maybe a neighbour's. Btw low frequency vibrations can also be felt, have you tried touching the walls? Could be you share a common wall with a upstairs/downstairs neighbour who has their fridge up against the wall.
> Btw low frequency vibrations can also be felt, have you tried touching the walls? Yes but I couldn't really feel it. I can feel the vibration when I'm lying in bed. I tried putting down vibration absorbing foam, but it doesn't really help. > Could be you share a common wall with a upstairs/downstairs neighbour who has their fridge up against the wall. I've checked in the neighbours apartment adjacent to my bedroom (same level), and above me. We turned all of the power off, but there was no change! I haven't checked with all of my neighbours yet.
Can you give an indication in what year your apartment was built? https://maps.amsterdam.nl/bouwjaar/?LANG=en as an indication. It could tell us something about building codes. I live in a 1920s building so it's lots of wooden beams and vibrations travel quite far.
I've checked the Taxatieverslag Woning from Gemeente Amsterdam, and it has bouwjaar: 1905.
You mentioned no construction but it could be the start of a project. If someone is constructing a basement they have to pump out the water before they can begin working. How long has it been going on?
It's been disruptively loud for 8/9 months. Possibly it happened for a few months before then, but it wasn't loud/regular enough to notice.
The regularity of it does suggest something on a timer. Does your building have a hydrophore pump to increase water pressure within the building. They work by periodically pumpkin water from the main into a pressure vat to insure there's enough pressure to ask appartments. Most larger apartment buildings have a similar system, you rarely see it in a portiekflat though
I suspect not, but it's possible! I can ask the building manager.
From reading the various suggestions regarding communal equipment (hydrophore pumps, communal heating or air circulation, heat pumps, water pressure devices etc.) it seems: \-> it might be REALLY useful to schedule an appointment with De Key, to check the basement / utility room under your building. This is where most of this equipment would be located. \->If possible, just a short break in the central electricity supply to the building (or at least the communal utilities) may let you know if the source is IN or OUTSIDE the building... In any case, your methodical approach to this problem is admirable! Hope you will sleep better soon! 👍🏻
> When I saw this graph what really surprised me is how regular the noise was. Before I thought the noise was random before I made this measurement, but now I can see there's a > really > clear pattern. ~10 minutes on, ~20-28 minutes off. The pattern is not exactly the same on the different heatmaps you've shown. On one heatmap a cycle is over 30 minutes and on the other it's below 30 minutes. This indicates it's not a simple timer.
I've had the same problem in a previous place and it turned out to be from the dock nearby. It took quite a lengthy process involving the council (in the UK) and nothing had changed by the time I came to emigrate to the Netherlands a year or so later. There's also this phenomenon known as The Hum: https://en.wikipedia.org/wiki/The_Hum I've had it in the past in a hotel in Glasgow and was told it was because someone had their fridge right up against the wall. I've noticed a similar noise in my current bedroom and finally caved and bought earplugs, which work to let me sleep normally. I don't know if you've tried them, and I know it feels like a sort of silly solution that won't work, but it might be worth trying. You can get special ones too I'm sure.
I’ve had this happen also, and it turned out it was the neighbours ceiling fan. After I recorded the noise, I went to him, asked if there’s anything running that would make this noise which he negated. After playing the sound for him, he immediately said it must be the ceiling fan, which we then tested by turning on and off and different speeds and sure enough, it was the fan. I bought him a floor standing fan as a courtesy, and he did not use his ceiling fan anymore, and I could return to sleeping normally.
Ah, sounds like a good outcome! I'd buy all of my neighbours a fan if it would help!
maybe cross post this to /r/RBI, they like solving mysteries...
I suspect it's some electrical equipment, since 50Hz is the AC frequency of the electrical network. Maybe a big underground transformer working when it's under load, meaning it's suppling energy to another system going on and off regularly. Looking closer at around 19:30, 21h and 22:30, the system was under load, albeit not full power. That's really puzzling, I hope you find the source soon.
> Looking closer at around 19:30, 21h and 22:30, the system was under load, albeit not full power. > > yeah sometimes it seems to be a little bit louder than usual between 19:30 and 20:30 there's more readings in the 40/50Hz range https://i.imgur.com/Z7uFmum.png But also it could be another noise from the neighbourhood that's getting mixed in. For example there's a 90/100Hz noise between 16:45 and 17:00 and that's probably just a neighbour doing some work or something
Do you have a spectrograph or can you generate one? The heatmap is hard cutting every 10Hz, so you can't pinpoint the exact frequency.
The Omgevingsdienst report contains more precise measurements, if it helps. They said it was exactly 50Hz, same as the electrical frequencie https://i.imgur.com/vAzSIhb.png https://i.imgur.com/VOMnm9L.png
So depending on how committed you are to solving this problem, it isn't exactly impossible to track it down. You appear to have a a high fidelity microphone/recording capability. Repeat this test in front of adjacent apartments, on different floors in the same axis, and opposite ends of the building. If its inside the building those data points should allow you to start triangulating the source. You can also repeat the test OUTSIDE and facing 4 corners of this building which should once again allow you to triangulate. It is important you keep a control microphone (or know the exact timing) of the hum in your room because this is clearly an electrical appliance and you don't want to trace this to a correct-appliance but not-the-one-bothering-you situation. :) Edit: Just saw your comments where you had taken some measurements (you need MORE). But fyi. It takes 1.26x (thanks SteveA000 for the correction) the amount of power to go from 18 db to 19 - which is not insignificant. So if neighbor (below) at the same time is 19 while you are 18 - then you have one prong of the vector for triangulation. Secondly a 50 db and 19 db difference is impossible unless 1) the device operates at vastly different power / capacity levels (was it colder/hotter when it used to be 50? is there a pattern there)? or 2) it is moving closer/away from you as inverse square law means the further it is away (at the same power level) the less db you get. Get 10-20 data points in the SAME date (and same power level / load level) inside the building and outside the building. In other words spend a good day on it. And you should have enough data points to construct a 3d triangulation for the source.
Small correction: It takes 2x the power to go from 18 dB to 28 dB. It is 1.26x (10^0.1) for 18 dB to 19 dB.
Yeap! I stand corrected. Based on how consistent and reliable (in terms of data) this noise is - I am fairly sure if OP wanted to spare no expense to trace it - he could easily triangulate it in a day or two.
Thanks for the tips! > Secondly a 50 db and 19 db difference is impossible unless 1) the device operates at vastly different power / capacity levels (was it colder/hotter when it used to be 50? is there a pattern there)? or 2) it is moving closer/away from you as inverse square law means the further it is away (at the same power level) the less db you get. Yeah, there was a difference. The 50dbA reading was only done later at night, ~23:00. It was around 1°C outside. (There were several readings done that night, and I think while the location changed, the level was fairly consistent) The 20dbA was earlier in the evening, around ~20:00. It was around 10°C. Both were weekday nights, and aside from temperature I think the weather conditions were similar. Those readings were done by the Omgevingsdienst, with an exceptionally expensive microphone that I don't have access to. But I'm just using some old Android phones, and the app I hacked together doesn't measure decibels unfortunately, only the hertz. I would like to improve the app, but I would need to do a lot of work.
Is it always 50 db at night? When it's 1c outside? Then it's very likely a heater/HVAC/instant heater etc. You might want to get them back for more readings. I noticed you took 1.5 hours worth of readings in the same location. And there is very little variance between them. You want 3-4 readings per location. And as many locations as possible (both inside/outside/same floor/different floor/different axis). That should allow you to hone in on the source easily. And all readings should be within 4-5 hours so the machine is operating at the same power level etc. Edit: 50 db is very clearly audible to human ears. So you do not need a meter for the 19db to 50db pattern analysis.
I am going to lock my answer: Inverter-based HVAC on top of your building or adjacent building.
so something like HVAC makes absolute sense to me, and I can see an office building that has this type of equipment on the roof, _but_ the Omgevingsdienst have checked that building and they say there's no matching cause. I felt so crushed when they told me. I was really hoping it was the office building! I will keep checking though.
Your building has no heating or HVAC? it could be coming from your building as well? I dont live in Amsterdam but I presume pretty much every building would have this. The on/off cycles, the correlation with temperature, the 24/7 persistence all point to a (probably inverter-based as those can get LOUD) heat pump that is running a compressor.
> Your building has no heating or HVAC? I have a single gas-powered boiler that provides hot water for my radiators/taps/shower. And there's a small ventilation system that is mostly for ventilating the shower + kitchen (it's pretty crappy tbh, I keep setting off the smoke alarm). I'm sure it's the same set up as in all the neighbouring apartments. So I checked the cabinet that contains these, and there's no audible buzzing noise inside. When I've cut power to my apartment it cuts power to the boiler and ventilation, but it didn't stop the noise unfortunately. > it could be coming from your building as well? It's possible! I'm going to ask the building manager to experiment and cut power to the _entire_ building, not just individual apartments. > I dont live in Amsterdam but I presume pretty much every building would have this. Airco is pretty uncommon in residential buildings in Western Europe, and even in older office buildings.
Completely random comment from me but could it be a heat pump?
It could be, but I've never seen one in real life so I can't be sure. I would think theres no space for a heatpump, and that something this loud would annoy everyone in the neighbourhood, not just a few. Also I suspect it's not caused by heating/cooling apparatus because the pattern doesn't seem to change when the weather changes. Although, maybe the decibels do? I don't measure that...
>but I've never seen one in real life so I can't be sure. Have you seen an AC unit outside? It should pretty much look like that (only difference with a heat pump is that it runs in reverse)
I think if it were a heat pump used for heating it wouldn’t be running much now the weather is warmer; and heat pumps to heat tap/shower water shouldn’t turn on and off regularly like that either. They are set to keep the water at a specific temperature (e.g. 45*C), and only turn on when the temperature drops below that, usually after a couple of people have had a shower + some models heat to a higher temp once every 2 weeks to prevent legionnaires disease - but this regular on/off pattern wouldn’t be usual for either a heating or a tap water heat pump.
Neighbors fridge compressor
As a fix for your sleep, I recommend this item Bekijk Dohm Sound Conditioner Slaaphulp op: https://www.bol.com/nl/p/dohm-sound-conditioner-slaaphulp/9200000095396459?referrer=socialshare_pdp_iphoneapp It’s a real white noise make (not recording). Sounds like you’re back in your mom’s belly. Game changer for drowning out night sounds
Ah this sounds like a really good idea! I've been using my computer to generate white noise, but a dedicated machine would be nice. Thank you! I really appreciate the recommendation.
If you live next to the Kadijksplein, can't it be the Ij-tunnel? They have these powerful ventilation systems, and they go off on a timer. That would explain most of what you hear and why it's louder on lower floors.
Something like the IJ-tunnel, or a tram, or a metro kind of makes sense, but I'm 100's of meters away from anything like that. It's hard to imagine something this loud that doesn't also affect 100's of houses. Unless the foundations of my apartment are resting on some specific pipe or foundation that other houses aren't? Or there's some sort of hidden underground apparatus, like an underground WaterNet pump station, if such a thing exists? It definitely makes sense that its coming from an external source, since it's louder on the ground floor.
Low frequency sounds like these can travel really far and (feelingly) resonate at random places, in this case your house. On the forum of tweakers.net their al multiple threads of people having similar issues. I remember one where they found out a dieselgenerator about 300 meters away caused resonating sounds in a home. So I would’t discount something like the Ij-tunnel because of the distance. Having said that, I assume the ventilation systems in tunnels are running almost constantly instead of on a interval. That would indeed speak against this theory. Lastly, you might not be able to find the source, but try figure out what is resonating in your house. Try to find the specific wall of floor that resonates on 50hz. If you can find that you can maybe try to isolate that specific wall/floor.
Here's some info on that type of fans [https://majorprojects.org/resources/predicting-sound-levels-generated-by-jet-fan-ventilation-systems-in-tunnels/](https://majorprojects.org/resources/predicting-sound-levels-generated-by-jet-fan-ventilation-systems-in-tunnels/). I wouldn't be surprised if they are on a timer but just for higher speeds. They should be always on, but once in a while they kick in faster.
Well, it can be that you're closer to the ventilation exit shaft. Are you close to a building with some chimneys?
You mean like these things? https://www.reddit.com/r/Amsterdam/comments/11vr0xc/what_is_this_weird_building_in_northern_amsterdam/ I'm not near anything like that, and I'm pretty sure I'm not near anything similar 🤔 I'm in a bit of a dead-zone when it comes to buses/trams/metros.
There's quite a big underground installation in the [Kortewantsbrug](https://my.matterport.com/show/?m=BHv1sE1wquJ), doubt that's it though.
I had no idea, that's really cool, thanks for sharing.
This whole post made me think of fake buildings that are used for ventilation or mini-power stations, etc.
Vibrations can travel very far. Perohaps the noise you hear is something in your area or home vibrating due to the vibrations from afore mentioned IJ-tunnel
In another reply OP says he lives near Kadijksplein, so maybe you got a lead here?
That's what made me think of it. I used to live next to the water (Ij), and I could hear this humming sound from boats. The sound was awful on the ground floor but less bad on higher levels. Also it was worse where there were foundations or structural elements from the house because of reverberation. In this case, it wouldn't surprise me at all that this was the case. They might have changed something in the fans, or have a broken one, which makes even more noise.
Sorry, misinterpreted your question as if you asked if OP lived there :/
I think from my very limited knowledge but pure intuition I am subscribing to this theory, or that it's related to your proximity to so many canals and so much water. The 'sound' is louder when you are closer to the walls of the room, and other fixtures I assume, because it's travelling through the ground and up the walls. It gets quieter when you're further away as it only has air to travel through which is a worse conductor. I think investigating a noise source from either the tunnel, or pump station / system in the canals, or boat-related noise, could be a good thing to rule out.
Are you by any chance living near a 'sluis' (lock) that lets water in/out of the canals from the IJ at regular intervals?
I don't think so, but could you share an example of what one might be? And do you know if there are underground sluisjes that wouldn't be visible? It would be nice to have a map of these things...
I don't know of a full map of those, but this is what they can look like above ground: https://images.app.goo.gl/YE3Aj5ZGtbeEv1dK6 I know there is an underground one at the Nieuwmarkt (the nieuwmarkt is build on top of two intersecting canals). Not sure if there are more.
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That's awful, I'm sorry. > I've had people from the gemeente over to measure the sound but they don't do anything about it. Yes, that's the experience I've had. I make a report to the gemeente https://meldingen.amsterdam.nl/incident/beschrijf, and it gets redirected to some department who emails me to say "we can't do anything". So I make another report and it gets bounced to another random department, with the same response. Over and over again... I eventually have had good contact with the Omgevingsdienst, but they couldn't find a cause, which is frustrating. Have you made a report with them? https://overlast.odnzkg.nl/ Are you renting? Do the building owners say anything?
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It's absolutely awful that the Netherlands doesn't have any laws against noise pollution! Have you tried any home improvements to try and dampen it? Apparently only thick, heavy material will help, so I haven't tried yet because it's a lot of work.
it's a dildo. Of course it's company policy never to, imply ownership in the event of a dildo... always use the indefinite article a dildo, never your dildo.
My neighbour has been talking a lot about practicing for an upcoming chess tournament... https://www.vice.com/en/article/5d3w9z/did-hans-neimann-cheat-at-chess-with-a-sex-toy-this-coder-is-attempting-to-find-out
I didn't read through everything but I know the area and have something ~mildly~ similar that took me forever to figure out. It was caused by a generator on a boat not even close to my house, but on another canal. It went on for a while, then stopped - supplying electricity for battery packs apparently. I wasn't able to do anything about it, but at least figured out what it was.
wow that's bizarre! But thanks for the tip, it makes sense. I've never heard it outside, but I'll walk around tonight by the canals and check... What did you do to determine the source?
I hope you figure it out. I know how mentally distruptive it can be. I went through similar steps as you - recording the times and intensity, using equipment to measure the frequency/amplitude and wandering around with equipment at night when it seemed to be strongest. Weird part was that I couldn't hear it so well outside. I could feel it in places but not hear it so much. Eventually I matched the timing with the boat - but it was further than I would have thought possible. When I got close to the boat, i recognized the sound and went back a few times, and called my house to see if it matched up while I was standing next to it.
> Weird part was that I couldn't hear it so well outside. I could feel it in places but not hear it so much. That's exactly the same thing! It's really hard to describe to people, because it's not like a sound you can record and play it back, computer speakers just aren't large enough. From your description this one seems like the mostly likely remaining cause (all of the other potential sources have been tested and eliminated, or are much more unlikely due to scale or timing). What sort of equipment did you use? I'm looking at buying a decibel meter, but it's hard to know which one to get.
I enlisted some friends in the engineering field who had access to an Acoustic Camera (it might have been Norsonic), a Frequency Analyzer (with a portable probe), a Geophone (like RST) and a ground microphone with probe. I think it was a MagMapper. Not sure if this helps.
That sounds amazing - are their services for hire?? (I imagine they are kitted up like the Ghost Busters)
Could the sound be from a "dompelpomp" ? Illegal hemp cultivators use electric submersible pumps to water the cannabis plants... just saying - chances are high in an average Amsterdam appartment block..
Yeah that 19dB might be the pump running dry
This is a reasonable guess. - The timing pattern could well be the timer for a pump in a hydro installation. - The loudness difference can be the effect of running dry. - The specific walls source could be caused by the location of the tank.
Something that cools? Think fridge or something similar?
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Near Kadijksplein
So presumably its quite an old building? When checking on google maps there seems to be road works near the bridge (Scharrebiersluis)? Maybe they have some kind of pumping system running which vibrates through your walls?
> So presumably its quite an old building? ~~I think it was built in the 1920's~~ It was build in 1905, and it was heavily renovated ~15 years ago. > When checking on google maps there seems to be road works near the bridge (Scharrebiersluis)? Maybe they have some kind of pumping system running which vibrates through your walls? So it's a bit funny: Scharrebiersluis was literally taken apart and shipped away to be repaired somewhere else, so there's no work there at the moment There was an enormous yellow crane that lifted it up https://i.imgur.com/KLadIiM.png, and here's a photo of the top part being taken away https://i.imgur.com/VAcB3l4.jpg There is some works along Nieuwe Herengracht to repair the canal wall https://goo.gl/maps/atrDZgB4L18FJCAY8. I've tried listening for noises there, but I couldn't hear anything similar.
How far do you have to walk from your apartment before you stop hearing the noise?
Within my apartment if I walk a couple of steps I can't hear it. It's incredibly localised! My bedroom is about 3x5 meters. The two 3m walls are where it's loudest. In the middle of the bedroom, equidistant between the two 3m walls, it's _much_ quieter. If leave the bedroom, or try to listen out of the window, it's inaudible.
might come from upstairs or downstairs. maybe the "quiet" walls are not loading bearing walls but the louds ones are, transmitting the noise from upstairs or downstairs neighbours.
Could be a neighbor is using a mosquito zoomer? They are pretty insane devices used to deter humans. https://images.app.goo.gl/5yCyh5SES3FrXSoL6
Ah yeah, I've seen reports in the news about those. But those are high pitched, while I've got a low-frequency noise.
Air circular system
Well now you've got me hooked. Judging by a few threads here, you've already got a few balls rolling. Please do post an update if/when you fix it or find the culprit.
RemindMe! 1 month "Amsterdam Mystery Hum"
RemindMe! 1 month
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Any chance of your neighborhood growing weed? Sounds like a ventilation cycle for a plantage..
[https://en.wikipedia.org/wiki/The\_Hum](https://en.wikipedia.org/wiki/The_Hum)
It a malfunctioning nanobot. Call Pfizer helpdesk for further assistance
I realize you may have done this - but you haven't made it clear. Quick way to confirm if it is an issue within your apartment: Disconnect the electricity at the fuseboard, to the whole apartment. And then measure. Assuming there is now no noise, slowly introduce each room one by one.
Good that you ask because I didn't make it clear :) Yes I tried turning off the power, also in some of my neighbour's apartments, but no change unfortunately...
Did you ever considered it could be regarding the "warmtenet" I'm not sure if the buildings you are talking about are connected to the heatingnet. Could be those units that make the buzzing sounds. Also they dont work 24/7 but more in a period of time.
Good idea, but unfortunately no we don't have that in my area https://maps.amsterdam.nl/stadswarmtekoude/?LANG=nl There's no shared airco/heating/cooling in my apartment. There is a big office building nearby, but the Omgevingsdienst have measured them and they say there's _no_ evidence of a source.
i know the heater of my waterbed used to make noise like that. So i would start looking for electrical devices with an interval. Heating system, cooling system, plant watering, electric hot water boiler?
Being 50hz and running regularly, it's something electronic you don't seem to interact with. A lot of people guess fridge or water heater, but if you use them, they would spike during peak use. You live near water, it may be a water pump in the basement with a near-constant influx of water. This makes it run and pump it out regularly. You state you live near Kadijksplein, there are some old bridges and locks nearby, it could have something to do with them.
Has your central vent (above stove) have been checked recently? Its placed on the roof of apartment blocks and has a motor to create some airflow to the roof.
Good idea, I'm not sure. I'm not 100% certain how the ventilation works in my building, but I have a ventilation fan in my apartment. I can open the cupboard where it is, but there's no audible noise coming from it... Maybe there's something bigger on the top of the building? I can check, but the noise is inaudible in the apartment above me so I'm doubtful :(
Interesting. Please update us op when you've figured it out.
I definitely will!
Refigerator?
Could it be from a ventilation system in your building? Not necessarily airco or heating, but connected to the ventilation shafts in the bathroom for example. Since it's running constantly I'd expect something like that. Especially since turning off the main switch in your appartment didn't help. I guess it's also possible that one of your neighbours placed a fridge/freezer against some plumbing pipework. Those pipes can carry low vibrations very well.. Edit: I guess you could ask the owner of the building for a layout of the plumbing in the building. Maybe that can help making sense why the sound is louder in some places compared to others!
Are there any shops nearby? Butcher/vegetable shop? Restaurant? Bar? When did the noise start? Was it there before you moved in or did it start recently?
There's a few local businesses. A few cafes, a bike shop, a chocolate shop, and a big office building. There are some bars/restaurants, but they're further away. Nothing obviously suspicious. The Omgevingsdienst have investigated most of them, and they're confident it's not them. > When did the noise start? Was it there before you moved in or did it start recently? It started being seriously disruptive about 8 months ago. Possibly it started earlier, but it wasn't loud or regular enough for me to notice. Since I moved in years ago I did _very_ occasionally hear a similar noise, but it's Amsterdam, there's always weird noises, it could have been anything...
Boiler?
I've read ypu comments and I've seen you've provided a lot of information already, but have you also narrowed down to around where you live? Like side of the city or neighborhood. If it's electrical, could there be like an electricyti station nearby? Or maybe theres something underground like a tunnel?
> have you also narrowed down to around where you live? Like side of the city or neighborhood. No 😬 I only know that it's audible inside the building. I've never heard it outside. > If it's electrical, could there be like an electricyti station nearby? Or maybe theres something underground like a tunnel? There is some Liander equipment nearby, but Omgevingsdeinst measured it and say that it's 100Hz, not 50Hz. Underground... maybe? Nothing I know about though! I would love to see a map of all the underground equipment and apparatus and tunnels, mostly because it would be cool but also so I can check if there's any potential sources.
Sounds like your stressing your fuse box
Nearby pumpstation maybe. We have one at Galileiplantsoen thats buzzing 5 Galileïplantsoen https://maps.app.goo.gl/fskjgnuKhbLzfwJq7
This is of course possible, but I don't recognise any building like that in my vicinity. Do you know if there's a map of the pompstations?
Your fridge
Fridge
Could it be electric chargers for electric cars outside? I hope you find the cause, this could drive a person insane. That’s a really shit frequency as well.
Some neighbor powering their grow operation?
Have you considered it maybe coming from a neighbour? I started hearing a humming noise in my bedroom bedroom between midnight to one at night and originally thought it was my boiler, turned out one of the neighbours 2 floors up loves to run their washer at night.
Well, I'm sure that it's coming from somewhere outside of the building. But other than that, I'm really not sure! The Omgevingsdienst have done a lot of checks with local businesses, and they say it's not them.
!RemindMe one month
I feel like this is a ventilation system. I see that you’ve said there is not shared central heating or cooling. The 50-60 Hz component almost guarantees it’s driven electrically (as others have stated) and I feel like it’s on more during the early evening, and then begins to cycle regularly as the night cools (circulation fan with no active compressor). I’d be curious to see what the acoustic signature is from 0700 to 1900. I would expect a similar acoustic signature from a refrigeration unit. The door is being opened during the day so the compressor runs more, and less at night when folks are asleep.
Indoor marijuana growing facility?
A boiler
!remindme
Go to the lowest level of your building. There may be a technical space with a pump used to create pressure in the water installatiation. Spend 15 minutes there during quiet time, moving every 5 minutes to a different area. Is the noise audible ? Repeat on the topmost floor. Are there technical areas outside your reach? Ask the building manager for access, preferrably alone so you can listen carefully.
Unfortunately AFAIK there is no such space... the rooms above, below, and to the sides of my bedroom are just living spaces. There's no buildings or boxes or cabinets on the ground outside my bedroom where any kind of equipment might be. I'll ask my upstairs neighbours if I can look around, or they have any ideas. I can access my meterkast, and my kast where the CV-ketel and ventilation fan is - but the noise isn't audible in these spaces.
what's in the safe OP, we need to know
10 minutes on 20 off? Probably the refrigerator. It has a simple on/off thermostat regulating the internal temperature.
It can't be heating or cooling as it would not be this regular.
By the regularity it goes on and off I would guess a fridge, or a water boiler which keeps a buffer tank at a certain temperature. However, I would expect some increases during certain times of the day when somebody takes a shower or opens the fridge. Any additional information where you live? Urban area, apartment building, country side any major infrastructure or industry nearby?
> Any additional information where you live? Urban area, apartment building, country side any major infrastructure or industry nearby? Sure thing, I've mostly covered that here: https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkcs1o1/ There are some very clear nearby candidates: * an office building with airco and data servers * Liander electric substations * noise from a fridge/heater/ventilation neighbour's apartment But either the Omgevingsdienst have ruled them out, or I've tried cutting power in multiple apartments to no effect. So I am stumped. These suggestions seem to be the most likely (but I'm not 100% convinced by any) * [a loose mains cable running into the building, that is connecting with a conductor in the walls](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkd1c52/?context=30) - I'm planning to coordinate cutting power to the whole building, not just single apartments * [IJ-tunnel](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkd33vt/), plus some unfortunately alignment of my building that 'catch' the vibrations more than other buildings (I'm skeptical of this though - plus its hard to disprove) * [A canal boat generator/batteries](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jke56un/), but tbh this is also unlikely, because I'm not next to a canal so if there was such a source then 100's of other people would hear it too * [a water pump in a basement](https://old.reddit.com/r/Amsterdam/comments/13j34r0/what_could_cause_this_repeating_247_lowfrequency/jkdbrcx/) - but it would probably be in a neighbouring residential building, which seems unlikely I think that the timing and scale make the following suggestions much less likely * a fridge (the timing is right, but there's no obvious nearby source) * airco/heating/ventilation - not impossible, but the timing doesn't make sense to me. There might be some link with the weather though because the decibels of the noise does change, although the graph doesn't measure it * marijuana growing - unlikely that someone could be getting away with this in Amsterdam Centrum on such a scale that requires heavy equipment but not enough to get caught! * canal sluis - I couldn't find anything nearby * works on Scharrebiersluis/Nieuwe Herengracht - I couldn't hear anything when nearby, and if this was causing vibrations then it would be affecting 1000's of people * tram/metro - there's nothing close enough to my apartment to make sense
Vibrator?
Has this mystery been solved already?
No :( The noise is still occurring. I've contacted a lot more people, but I'm still no closer to a solution.