Good Evening
I live in an apartment, my neighbor downstairs has his ceiling fans on very often. This is because he has a cat and this is how he deals with the litterbox smell. Lets assume he is not going to change his habits.
The fans, one in particular (bathroom) resonate through most of my apartment, wood floors and walls really help the sound travel. Before I poison his cat (joking) I had this idea tonight.
What if I put a microphone in one wall (there are some plumbing access ports) and learn how to do the whole noise cancelling thing (bose/aviation earphones come to mind). measure frequency and amplitude and send reverse polarity signal to speaker mounted to wall.
Let me hear what you think. The sound coming from the fan seems very constant frequency and amplitude.
-Shawn
I live in an apartment, my neighbor downstairs has his ceiling fans on very often. This is because he has a cat and this is how he deals with the litterbox smell. Lets assume he is not going to change his habits.
The fans, one in particular (bathroom) resonate through most of my apartment, wood floors and walls really help the sound travel. Before I poison his cat (joking) I had this idea tonight.
What if I put a microphone in one wall (there are some plumbing access ports) and learn how to do the whole noise cancelling thing (bose/aviation earphones come to mind). measure frequency and amplitude and send reverse polarity signal to speaker mounted to wall.
Let me hear what you think. The sound coming from the fan seems very constant frequency and amplitude.
-Shawn
Most extraction fans do drone.
Most extractor fans are also dead cheap.
I believe most of their noise is resonance from being mounted to 'wobbly' plasterboard.
some are quieter and better balanced/built than others.
Personally if your getting that much noise from others, I'd look at having a calm coffee and chat with him/her.
See what can be done about fixing the source of the noise.
Invite them around to your place so they can hear the noise for themselves.
They probably have no idea about it.
Without knowing how the building is built etc...
1. look into a better/quieter extractor fan, maybe even one that mounts to the outside wall of the apartment then run the vent tube from that.
Maybe theres a window mounted unit they could use instead.
2. ceiling fans, if their the rubber mounted maybe the bushes need replacing or lubricating, if their later ones with plastic swivel balls, maybe they need a smear of grease.
3. wont happen, but maybe the owner could look into some sound insulation between floor/ceiling.
Most extractor fans are also dead cheap.
I believe most of their noise is resonance from being mounted to 'wobbly' plasterboard.
some are quieter and better balanced/built than others.
Personally if your getting that much noise from others, I'd look at having a calm coffee and chat with him/her.
See what can be done about fixing the source of the noise.
Invite them around to your place so they can hear the noise for themselves.
They probably have no idea about it.
Without knowing how the building is built etc...
1. look into a better/quieter extractor fan, maybe even one that mounts to the outside wall of the apartment then run the vent tube from that.
Maybe theres a window mounted unit they could use instead.
2. ceiling fans, if their the rubber mounted maybe the bushes need replacing or lubricating, if their later ones with plastic swivel balls, maybe they need a smear of grease.
3. wont happen, but maybe the owner could look into some sound insulation between floor/ceiling.
I appreciate the response.
I have chatted with him, he used to keep it on almost constantly. Now he turns it off most nights, and is turned off during parts of the day. I think this is as good as it gets.
He is not handy and is really not too interested in doing anything more than he currently has, which he wasn't too interested in in the first place. If he was a different type of person and I could get into his apartment you bet I would put some rubber gaskets/bushings in there and I bet I wouldn't be posting here tonight.
But the situation is that I have to solve it on my end. I spend hours upon hours studying in my apartment, and I want to solve this.
I have chatted with him, he used to keep it on almost constantly. Now he turns it off most nights, and is turned off during parts of the day. I think this is as good as it gets.
He is not handy and is really not too interested in doing anything more than he currently has, which he wasn't too interested in in the first place. If he was a different type of person and I could get into his apartment you bet I would put some rubber gaskets/bushings in there and I bet I wouldn't be posting here tonight.
But the situation is that I have to solve it on my end. I spend hours upon hours studying in my apartment, and I want to solve this.
Hmm. ok.
Well, I don't think noise canceling on the scale your thinking of would be feasible.
And it sounds like the noise infiltrates your entire apartment.
Is there any sort of building manager or body corporate you can ask to look into it ?
Only options I can think of, in no particular order.
Shift.
Heavy floor treatment (thick rubber matting with thick wool carpets and second floating floors maybe)
Construction options (lift floor, fill floor space with rock wool etc, relay different floor materials, poor a layer of concrete).
Noise canceling headphones.
Play background music at a level that masks his noise.
Find somewhere else to study.
All depends on how much money you can poor into this. And if you own or rent.
Honestly, It's obvious the building needs serious works done to it to make it a better place for all residents.
It simply becomes an issue of money vs time vs how bad the noise bothers you.
One other option springs to mind.
In the 80's you used to be able to buy huge 'personal chairs'.
Big egg like things that you sat in. I remember those were awesome for killing noise and creating a 'personal oasis'.
Well, I don't think noise canceling on the scale your thinking of would be feasible.
And it sounds like the noise infiltrates your entire apartment.
Is there any sort of building manager or body corporate you can ask to look into it ?
Only options I can think of, in no particular order.
Shift.
Heavy floor treatment (thick rubber matting with thick wool carpets and second floating floors maybe)
Construction options (lift floor, fill floor space with rock wool etc, relay different floor materials, poor a layer of concrete).
Noise canceling headphones.
Play background music at a level that masks his noise.
Find somewhere else to study.
All depends on how much money you can poor into this. And if you own or rent.
Honestly, It's obvious the building needs serious works done to it to make it a better place for all residents.
It simply becomes an issue of money vs time vs how bad the noise bothers you.
One other option springs to mind.
In the 80's you used to be able to buy huge 'personal chairs'.
Big egg like things that you sat in. I remember those were awesome for killing noise and creating a 'personal oasis'.
A floating floor is going into the living room.
-Top-
Area rug
Thin hardboard
Underlay
2 layers drywall with green glue between
Underlay
-Bottom-
I believe that should cut out some general noise between floors, I'm not looking for studio isolation, just some piece of mind.
It's expensive, I am also designing up a bedframe the kind of does what you are talking about, encapsulates and isolates. (I also have a main strip just out my window) I just have to make it practical.
Landlords don't care, and moving isn't an option. I have almost the best I can get for this price in this city. I am top floor corner suite in the neighborhood of my choice at the top of my budget.
It's just that constant drone travelling through the wood frame.... If one fan could make that much sound do you not think one of those 'turn any surface into a speaker' could produce the same sound out of phase and reduce the amplitude?
I think I am going put some more thought into this....
-Top-
Area rug
Thin hardboard
Underlay
2 layers drywall with green glue between
Underlay
-Bottom-
I believe that should cut out some general noise between floors, I'm not looking for studio isolation, just some piece of mind.
It's expensive, I am also designing up a bedframe the kind of does what you are talking about, encapsulates and isolates. (I also have a main strip just out my window) I just have to make it practical.
Landlords don't care, and moving isn't an option. I have almost the best I can get for this price in this city. I am top floor corner suite in the neighborhood of my choice at the top of my budget.
It's just that constant drone travelling through the wood frame.... If one fan could make that much sound do you not think one of those 'turn any surface into a speaker' could produce the same sound out of phase and reduce the amplitude?
I think I am going put some more thought into this....
Yeah i dunno.
trying to 'fix' a floor/ceiling is past my abilities.
If your handy, and the other guy is amenable.
Maybe see if you can find a better extractor fan and offer to fit it for him.
maybe see about improving the mounting system while your at it.
most of these fans are prewired with a plug, so should just be a simple matter of removing, unplugging, and replacing it.
Only other thoughts I have are look at getting in an engineer that deals with noise isolation.
trying to 'fix' a floor/ceiling is past my abilities.
If your handy, and the other guy is amenable.
Maybe see if you can find a better extractor fan and offer to fit it for him.
maybe see about improving the mounting system while your at it.
most of these fans are prewired with a plug, so should just be a simple matter of removing, unplugging, and replacing it.
Only other thoughts I have are look at getting in an engineer that deals with noise isolation.
Once the vibration is in the structure itself, it's going to be extremely difficult to isolate yourself from it. From your persepective, the sound source is diffuse and all around you. There is no practical sound-cancelling technology that is going to give you what you want, other than headphones.
I too think your best chance is to kill it at the source. I have owned many ceiling fans in my day, and they vary widely in quality and performance, usually in direct proportion to price. For all the ridiculous plans you are considering, you could buy that guy one killer ceiling fan. Maybe $200 installed max, vs turning your entire apt into a home recording studio.
I too think your best chance is to kill it at the source. I have owned many ceiling fans in my day, and they vary widely in quality and performance, usually in direct proportion to price. For all the ridiculous plans you are considering, you could buy that guy one killer ceiling fan. Maybe $200 installed max, vs turning your entire apt into a home recording studio.
If your renting, try talking to the landlord about getting into your neighbors apartment to fix the source, maybe even threaten moving out. If it's a condo and you have a strata try complaint to them. There maybe other neighbors that have the same problem, strength in numbers. Noise canceling in a room is practically impossible.
Permanent solution
simon7000's suggestion prompts me to revise my advice. I suggested "kill it at the source", referring to the fan. But of course the source isn't the fan; it's the cat. I suggest placing the 200 pounds of kitty litter in the neighbor's kitty litter box. This should take care of the problem for at least a few months. For a permanent fix, place the kitty in the kitty litter box first, then place the 200 pounds of kitty litter in the kitty litter box.
simon7000's suggestion prompts me to revise my advice. I suggested "kill it at the source", referring to the fan. But of course the source isn't the fan; it's the cat. I suggest placing the 200 pounds of kitty litter in the neighbor's kitty litter box. This should take care of the problem for at least a few months. For a permanent fix, place the kitty in the kitty litter box first, then place the 200 pounds of kitty litter in the kitty litter box.
I am afraid you are jumping ahead.
Most ceiling fans have multiple speeds. At the highest speed I would expect a power draw of under 200 watts. As the motor should be at least 80% efficient that would leave 40 watts of losses. These are typically 1/2 electrical and 1/2 mechanical. So that would leave 20 watts.
The fan rotation speed would not be the 1800 rpm of a normal motor but fans are generally limited by code to 500 rpm or less.
That should allow us to model the fan as a 20 watt or 146 dB noise source at 8 hertz. Now the threshold of hearing at that low of a frequency is probably above 100 dB. (You more likely would feel the vibration.)
It is more likely the annoying sound is a harmonic. To get up high enough in frequency to be significant would be at least the 5th harmonic. This should be around 30 dB down from the fundamental or 116 db at the source.
The ceiling below will provide some attenuation but not the normal 20 dB minimum as the fan mount junction box should be tied to a floor joist. The floor however does provide both distribution loss of the noise and attenuation of 30 dB ish. The distribution loss would depend on the source size versus the moving floor area. So a 6" square box in a 10' x 10' room would be 400 to 1 or another 26 dB. That would put the noise level around 60 dB. When the fan is running at full speed.
At the worst case that would be past the normal annoyance threshold. The threshold is interesting because once past it you actually have to go at least 10 dB below it because the receivers have become sensitized.
It is more likely the noise is actually above this due to resonances in the structure. It is these and the harmonics that can be handled by a loose fill noise barrier. The low frequency vibrations cause the fill to move. This movement absorbs energy and transfers much of it to higher frequencies that are easily absorbed.
So placing 200 pounds of kitty litter still in the bags on the floor spread out above the fan location will quickly demonstrate a possible solution to the problem.
Now to do a noise cancellation would require a transducer such as a "Butt Kicker" bolted to the floor and an adaptive DSP system with an input transducer. Probably could be made to work. But way more money.
So try the kitty litter on the floor and if that doesn't work give it to the neighbor. The get a broomstick and pound on the floor every night as soon as he falls asleep. Get him to move!
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Well in that case....
Residential exhaust fans are designed to be low noise and are even marketed by noise level. If that is the type then carpet is the usual answer. But the big issue is unseen penetrations. One needs to poke around the baseboards, window frames, plumbing penetrations and ceiling with a can of foam making sure there are no gaps.
I would not expect such a fan to be a concern other than where it has it's intake.
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