Sound cancelling speakers in bedroom for traffic

[lordvader88]

I looked around on the net for a few minutes, can't seem to find much hope. Are there any consumer products out there, not headphones, speakers, that could help reduce traffic noise in a room ?

I'm considering moving to a place right on a busy street. I don't want to go crazy, yet.

[Howardlong]

I looked around on the net for a few minutes, can't seem to find much hope. Are there any consumer products out there, not headphones, speakers, that could help reduce traffic noise in a room ?

I'm considering moving to a place right on a busy street. I don't want to go crazy, yet.

I'd move then! ISTR this has been recently discussed somewhere, but I can't immediately find the thread.

It's a physics problem. The way noise cancelling headphones work is a mixture of isolation, plus the magic active noise cancelling sauce that provides a precise inverted waveform. That inverted waveform is a 180 degree inversion based on what it hears at each ear, and is introduced at a precise volume (together with what you're listening to). As soon as either the sensing microphone or the inverted signal are moved away from very close proximity to the ear, all bets are off, it's no longer possible to correct the constructive and destructive interference of the sound waves, which are coming from several directions.

Even with ANC headphones, as the wavelength shortens (i.e., higher frequency), the noise cancelling effect reduces, because trying to accurately align that 180 degree inverted signal becomes more demanding.

In practical terms, occasionally I wear a pair of Bose noise cancelling earbuds if the outside noise is too high for whatever reason (I live in the middle of London, sometimes it's noisy), and these work really pretty well in most instances, certainly traffic noise for example. The problem is whether you can cope with the slight discomfort of the buds in your ear. I don't much like the over ear Bose, the three or four pairs I've had  have a history of feeding back if you try to wear them while sleeping.

So noise cancelling speakers aren't practical. Having said that you've given me a great idea for a flexible funding Indiegogo campaign!

[In Vacuo Veritas]

You need STC rated window panes, 48 or above, professionally installed. Or you can add a second inner window pane over the existing one. Either way, you're looking at thousands of dollars. At least also get EER windows to cut on the heat gain in summer, and heat loss in winter.

[sokoloff]

A white noise generator will help to some degree. I don't believe that broad location (whole room) active noise cancellation is practical.

Mass and air gaps will be a good first step; white noise a secondary supplement. We live right on a 4-lane parkway. On the first and second floor (with double pane windows) and a fence in the line of sight to the roadway surface, the noise is barely noticeable and easily ignored. On the third floor (single pane windows and more of a view "over" the fence), the traffic is easily noticed.

[jmelson]

A white noise generator will help to some degree. I don't believe that broad location (whole room) active noise cancellation is practical.

Mass and air gaps will be a good first step; white noise a secondary supplement. We live right on a 4-lane parkway. On the first and second floor (with double pane windows) and a fence in the line of sight to the roadway surface, the noise is barely noticeable and easily ignored. On the third floor (single pane windows and more of a view "over" the fence), the traffic is easily noticed.

Well, there's your answer, then!  Move to the basement, and you won't be able to hear anything except the fire trucks.

Jon

[DerekG]

A white noise generator will help to some degree.

Quite right. My brother was a policeman for many years, working night shift for 2 weeks at a time.

He used a white noise generator so he did not hear the kids from the school across the road at recess & lunchtimes.

It generates a constant wide spectrum noise that drowns out the outside noise. Adjust the volume to "just" drown out the annoying noises from outside. Stick with it for the first few days/nights until you get used to it.

[Zucca]

Sound cancelling works only with constant spectrum noise. It is impossible to delete the unpredictable truck noises passing on the road.
Isolation/damping is the only cure:

[In Vacuo Veritas]

Sound cancelling works only with constant spectrum noise. It is impossible to delete the unpredictable truck noises passing on the road.
Isolation/damping is the only cure:

Took me a while to realize these go in the ear, not the r....

Was wondering how sitting on these would reduce noise.

[metrologist]

LoLzzzzzz


https://www.kickstarter.com/projects/1280803647/muzo-your-personal-zone-creator-with-noise-blockin

[CatalinaWOW]

While I understand and agree with the objections to large area noise reduction, there must be some possibilities in this area.  Several modern cars use active noise cancellation to reduce cabin noise and by all reports it is at least somewhat successful.  I don't know how they do it, but do know that in one example I sat in there were multiple sound pickups and emitters involved.  The systems are highly engineered for the vehicle so not the kind of thing you would buy and install in a room.

Something that might appeal to members of this forum would be to implement active damping on the windows using an accelerometer and voice coil driven free mass.  Or maybe multiples.  Increasing the effective mass of the glass would do wonders for the noise level.

[BrianHG]

LoLzzzzzz


https://www.kickstarter.com/projects/1280803647/muzo-your-personal-zone-creator-with-noise-blockin

This piece of junk should be in the Dodgy Technology section.

[BrianHG]

Here is the official thread:
https://www.eevblog.com/forum/chat/neighbours-children-driving-me-mad!/

[fonograph]

This might help. http://www.psiaudio.swiss/avaa-c20-active-bass-trap/

[kuriisenbo]

This is also a very big problem for me. I live on a busy street where there are cafes that are open until 11 PM. 
When I come home from work I want to rest, which I can't do because of this noise. So, I decided to make noise insulation in my apartment, because I can't live like this anymore. I feel constantly tired and I already have problems at work because of this situation. That's why, I have already installed soundproof windows that have solved my noise problem by 30%. I also want to make a soundproof ceiling and here rockfon.co.uk I found ceiling panels that should help me get rid of noise. If someone has already had this experience, please give me some tips.

[jogri]

This is also a very big problem for me. I live on a busy street where there are cafes that are open until 11 PM. 

I would start with soundproofing the windows, you can either use thick theatrical curtains (the velvet type) or go straight for the mass loaded vinyl sheets. Just hanging them like normal curtains won't suffice, you have to create an airtight barrier between the window pane and the curtain: Use velcro around your window frame to hold them onto the wall, make sure there are no airgaps. (You can also buy vinyl/fiberglass sheets for your windows, but they come in at ~500 bucks per window).

[ConKbot]

While I understand and agree with the objections to large area noise reduction, there must be some possibilities in this area.  Several modern cars use active noise cancellation to reduce cabin noise and by all reports it is at least somewhat successful.  I don't know how they do it, but do know that in one example I sat in there were multiple sound pickups and emitters involved.  The systems are highly engineered for the vehicle so not the kind of thing you would buy and install in a room.

Cars have the occupants heads in a relatively consistent spot, so for lower frequencies, it's is doable. Add a bevy of microphones, do simulation and measurements of sound in the interior, bake that down into something more simple to let the sound DSP run, and you can make 2 quiet zones near the headrests.

[Howardlong]

While I understand and agree with the objections to large area noise reduction, there must be some possibilities in this area.  Several modern cars use active noise cancellation to reduce cabin noise and by all reports it is at least somewhat successful.  I don't know how they do it, but do know that in one example I sat in there were multiple sound pickups and emitters involved.  The systems are highly engineered for the vehicle so not the kind of thing you would buy and install in a room.

Cars have the occupants heads in a relatively consistent spot, so for lower frequencies, it's is doable. Add a bevy of microphones, do simulation and measurements of sound in the interior, bake that down into something more simple to let the sound DSP run, and you can make 2 quiet zones near the headrests.

Won't work. Ears are too far apart, 180 degrees apart at about 800Hz. one ear will have constructive interference, the other destructive interference. Noise cancelling only works practically in the very near field.

[cdev]

I can testify to the effectiveness of triple paned (in my case argon filled) windows for noise reduction (and privacy during the day) The reduce sounds around 30 db. But they arent THAT expensive. At least mine werent. And they were custom built. Shop around.  You can use a pink noise generator to mask sounds. I used to use a fan or tv noise back when they had analog tvs. Also soft foam earplugs and sound absorbent egg style board on the walls.. (it eats up sound)

Thank God that I don't have to live like that anymore. I used to have to work at night and sleep in the day. It was fun but it also led to chronic sleep deprivation.

You need STC rated window panes, 48 or above, professionally installed. Or you can add a second inner window pane over the existing one. Either way, you're looking at thousands of dollars. At least also get EER windows to cut on the heat gain in summer, and heat loss in winter.

[Berni]

Forget about it. canceling wont work without headphones because the speed of sound is simply too slow.

If you have old windows just simply replacing the rubber seal around the edge will make a big difference, easily >10dB because the rubber gets old and hard so it doesn't conform properly and seal. This also helps with your heating bill in the winter. Just simple double pane glass windows can stop a lot of sound if the seals are in good state.

But if you upgrade the entire window to a good modern triple pane window you can get the room so quiet its uncomfortably silent. They are not that expensive, few hundred bucks for a regular standard window with installation.

We did both of those upgrades on our house, the new rubber seals made a big difference and new windows even more. To the point that once we had a truck deliver some gravel behind the house and some time later someone steps outside to find the big pile of gravel has mysteriously appeared while all 3 family members ware at home. Nobody did hear the truck back up into the yard and dump it, the truck driver didn't come up to the front door because he already knew where we wanted the gravel dumped. They work THAT well.

And yes having a room with a lot of echo will make the noise easily seam 4 times louder than it is. In those cases simply hanging a curtain or putting some foam on a wall can make a very noticeable difference.

[LaserSteve]

If your dealing with reflected sound in the house:

Owens Corning 703 is your friend. Acoustic Cloth to wrap the panels in,  comes from Guilford of Maine.   Also Roxul Safe and Sound or Quiet-Batt if you can put it in the walls.

      Break the corners of the room with acoustic treatment so they do not act as corner reflectors, and damp the ends and sides of hallways so they do not act as waveguides. In the right place, a few panels of adsorbing material can do wonders, but it takes some work. Leave an air gap between the panels and the walls if hung, of about 3 mm.   Grids of panels with half wave spacing at the frequency of interest can reduce costs over covering the whole wall for reflection mode damping.

Wood lattices aka  "acoustic wood panels" can be decorative  and scatter or adsorb  the sound. But they have to be tuned.  There is a great deal of info out there on making home music studios soundproof and echo proof. Start there. 

I've found that often you do not have to treat whole walls if your willing to do a bit of wave math.  Right now I'm listening to a woman in the kitchen,  scraping plates from twenty feet away, The sound is guided  down a hallway to my  bedroom.  So maybe it is time I put some panels in the hall.

My bedroom is 60 feet from a busy street, with a classic wooden house, given time, you simply get used to it, and your brain looks for differences in the pattern to wake you, not waking on every loud muffler that goes down the street. During the day, however, it gets annoying.

The living room has a new, massive,  multi pane, PVC framed window.  It is wonderfully quiet in there compared to the aluminum framed windows with the classical glass.  The reduction in the heating bill and noise was noticeable when we replaced that window, the wooden garage doors, and a large sliding glass door with the newer technology. Here in cold Northern Ohio, the payback was noticeably quick.


  However in this case White Noise is a good idea. 

Steve 

[Masa]

Actually active noise cancellation does work even in bigger size than the headphones. It's just that you cant of course achieve it everywhere in the space simultaneously, you will have certain spots in the space where you have the destructive interference and there it works, but if you move elsewhere in the space where the waves add together, there it actually increases the sound.

But when you are sleeping, your head usually is in one well known location. So it might actually work somewhat well for sleeping.

It is for example nowadays used in turboprop aircraft for reducing the noise in the cabin with speakers.

The bigger the space, the lower the highest frequency at which it works somewhat well. So with headphones you can practically cancel much higher frequencies what you can in open space.

https://www.diva-portal.org/smash/get/diva2:838339/FULLTEXT01.pdf

Of course, this aircraft case is easier than cancelling out passing traffic nosie, because the sound source is well known and even information about the engine can be used for tuning the cancellation.

[Howardlong]

It is for example nowadays used in turboprop aircraft for reducing the noise in the cabin with speakers.

The bigger the space, the lower the highest frequency at which it works somewhat well. So with headphones you can practically cancel much higher frequencies what you can in open space.

https://www.diva-portal.org/smash/get/diva2:838339/FULLTEXT01.pdf

Of course, this aircraft case is easier than cancelling out passing traffic nosie, because the sound source is well known and even information about the engine can be used for tuning the cancellation.

82Hz, ~4m wavelength. The harmonics would be harder, but the fundamental can be dealt with assuming enough density of loudspeakers.

As others have said, passive techniques are far, far more practical in the OP’s case.

I live on a main road, and the difference that secondary (as opposed to double) glazing makes is astonishing.

[raptor1956]

ANC is limited both spacialy and by frequency.  Moving even a little would require the cancelling sound to change as well so getting this to work in a whole room isn't really practical.  It's a sure bet that you could lower, slightly, for most of the room, but there's likely be areas where the sound is amplified.  Also, ANC works best with lower frequencies and hardly at all with higher frequency transient sounds.

This is a problem that I am currently dealing with -- I live in an apartment and work a night shift which means trying to sleep during the day with the sound of lawn mowers and leaf blowers and the neighbors yelling at each other.  I have a particular problem with my next door neighbor as there young daughter has no inside voice.  It may be that she has Tourette syndrome or something similar, but she simply does not speak at normal conversational levels AND punctuates nearly everything she says with a vocal manor involving screeching.  So, we have a loud neighbor uttering transient high frequency sounds throughout the day and since we're still on lockdown and school is out for the year she's home ALL DAY.  My bedroom shares a common wall with the very room she spends much of her time so sleeping there is ... impossible.  I've been forced to setup a temporary bed in my office which is at the other end, furthest away, from the common wall.

Sleep deprivation is not fun!


Brian

[ConKbot]

While I understand and agree with the objections to large area noise reduction, there must be some possibilities in this area.  Several modern cars use active noise cancellation to reduce cabin noise and by all reports it is at least somewhat successful.  I don't know how they do it, but do know that in one example I sat in there were multiple sound pickups and emitters involved.  The systems are highly engineered for the vehicle so not the kind of thing you would buy and install in a room.

Cars have the occupants heads in a relatively consistent spot, so for lower frequencies, it's is doable. Add a bevy of microphones, do simulation and measurements of sound in the interior, bake that down into something more simple to let the sound DSP run, and you can make 2 quiet zones near the headrests.

Won't work. Ears are too far apart, 180 degrees apart at about 800Hz. one ear will have constructive interference, the other destructive interference. Noise cancelling only works practically in the very near field.

I would assume in the cars Catalina mentioned, the active noise cancellation is for lower frequency rumble, road and engine noise. The higher frequency stuff  can be handled with traditional damping, but trying to block sub 1-200 Hz with physical materials would be heavy.  The higher end vehicles with the camera that watched the driver to see if they are dozing (not sure if that is a thing still? ) could get more accurate information on at least the drivers head location.

EDIT: Or if its VW / BMW, they could just turn off ('Cancel') the box that makes vroom vroom noises ("active sound") in the passenger compartment.

[Marco]

I wonder if you could make a whole wall an active sound canceller for an arbitrary incoming sound field. Or rather, I wonder if you could do so cheaply. The wavelength of sound is so short for the medium frequencies that the density of sensors/actuators seems to be the rock on which the idea breaks.

The attraction is that you could make it light and relatively thin compared to passive insulation ... but doesn't seem worth the very high cost.