9
votes
Accepted
What device is this, and how does it work?
Something like this?
http://www.browninnovations.com/sound-dome/single-localizer-sound-dome
As others have said, it is a speaker with a parabolic reflector to direct the sound down at the listener. ...
- 766
8
votes
Will a short brick wall help shield against bass or will it go around?
The wavelength of sound at 40Hz is about 28 feet.
However tall the wall is, the sound will diffract over the top of it and spread downwards on the far side.
If you made the wall about 5 wavelengths ...
- 12.6k
8
votes
What device is this, and how does it work?
With a description as vague as that, it was probably a parabolic reflector with a speaker at its focus. Pointed straight down, the "beam" of acoustic energy would be reflected from the floor right ...
- 6,984
6
votes
How to build apartment floors/ceilings to not transfer sound?
There's a few ways that engineers quantify sound passing through ceiling/floors:
Impact Insulation Class (IIC)
Outdoor/Indoor Transmission Class (OITC)
Sound Reduction Index (SRI)
Sound Transmission ...
- 225
5
votes
Can ultrasonic sound pass through solid medium?
Ultrasound partially reflects when it encounters a medium with different acoustic impedance. It behaves like light and obeys Fresnel equations. If the angle of incidence is smaller than the total ...
- 1,035
4
votes
Accepted
Is my procedure applicable to make a room soundproof?
If I am understanding your question correctly you want to surround your room a vacuum so sound waves will not travel through your glass walls. In theory this would work very well but there are some ...
- 593
3
votes
Simplest way to reduce low frequency noise from windows
From your troubleshooting it does sound like the window is resonating. Below is a good visualization of one potential vibration mode from the Vibration of plates Wikipedia article. The mode for your ...
- 8,285
3
votes
Simplest way to reduce low frequency noise from windows
Some thoughts on your problem: have a look at the physics behind "Chladni plates" - your window pane will act as a passive speaker at 166Hz but not in a "pumping" fashion like a ...
- 31
3
votes
Reducing vibration coming from the floor while at sleep
I would try the cheapest way first - sleep on the stacked up mattresses without frame, nor box spring, to increase the effect of damping. A thick wall to wall carpet underneath will provide extra help ...
- 8,232
3
votes
Reducing vibration coming from the floor while at sleep
Apart from the other two valid options (rubber pads and anti-vibration mounts) another (maybe less expensive) option would be to increase the mass which is attached on the bed.
effectively you would ...
- 24.3k
3
votes
How to build apartment floors/ceilings to not transfer sound?
Layers.
Here's a reference. They are trying to sell you a service (installing soundproofing), but they do a better than average job of explaining what they propose to do. I have no affiliation with ...
- 131
2
votes
Will a 3-wall acoustic barrier work or will sound go around?
For fans used to move air, their primary noise radiation frequency will be (number of blades) x (revs per second of the fan shaft) and will be emitted in all directions if the fan shaft is vertical, ...
- 15.3k
2
votes
Will a 3-wall acoustic barrier work or will sound go around?
It will help to shield you from direct high pitch noise waves. because these waves short wavelengths will be blocked by objects in the range of your partition size.
Say a noise of frequency of
500-...
- 22.8k
2
votes
Accepted
Using the bitrate value on a calculation is causing contradiction, why?
Because the file is compressed. The sample rate and bits per sample are parameters of playback after decompression. The file size is for the compressed format, the amount of data that needs to be ...
- 6,115
2
votes
Reducing vibration coming from the floor while at sleep
I would say it's the entire building, including your ceiling and even the foundation of the building that is vibrating. I have seen even the sidewalk shaking.
Remedies can be very elaborate and costly ...
- 22.8k
2
votes
Reducing vibration coming from the floor while at sleep
It's difficult to say what will work in your situation. I think some trial and error might be involved.
Constructing a frame and hanging the bed as you suggest could work but I would vibration dampers ...
- 9,752
2
votes
Accepted
Will a short brick wall help shield against bass or will it go around?
You may try to build something like highway sound barrier. They say that modified acrylic sheet is the best material for this, and I guess it's cheap.
Other option is not to build wall, but to ...
- 36
2
votes
Will a short brick wall help shield against bass or will it go around?
Short frequency noise will tend to go around and even through objects, soil, or foundations to your home, as base humming sound.
For 40 hertz or wavelengths of 5-10 meter object of the sizes of the ...
- 22.8k
2
votes
Reducing vibration coming from the floor while at sleep
Here is an antivibration mount which will probably work, and is cheap:
Get you four small inner tubes (as used in wheelbarrows or small garden wagons, hand trucks, etc. and inflate them about half-...
- 15.3k
2
votes
Microphone angled waterproofing
You could make a water drain trap. Drill a vertical hole that meets the microphone hole somewhere along its length, with a drain hole sloping down for the water to escape. You could then make a step ...
- 12.6k
2
votes
Reducing vibration coming from the floor while at sleep
A number of years ago I was in a similar situation. As kamran says, the entire building is involved.
Before going further, I would point out that whether or not you are able to ignore it / whether ...
- 1,551
2
votes
Reducing vibration coming from the floor while at sleep
TLDR: hammock
The woman below me and my husband purchased the exact same device you pictured to torture us with. It seems she snapped during lockdown as it was much more quiet than usual in our ...
1
vote
Most sound proof earmuffs in the world
None.
High-quality hearing protection already reaches the limits of what earplugs or earmuffs can provide. The remaining sound is transmitted through your body, so any further improvements would ...
- 344
1
vote
Secondary glazing 16 to 20cm away from double glazing
You'll introduce another coincidence dip at 60 Hz (roughly) but gain about 4 dB more attenuation across rest of the frequency range, from the mass loading effect, assuming all panes are the same ...
- 902
1
vote
Reducing vibration coming from the floor while at sleep
I know there was someone who had a few blog posts about a similar issue and ultimately settled on low-cost anti-vibration pads.
Myself, I was theorizing if one could float a bed frame on a thin layer ...
- 111
1
vote
Accepted
Creating an isolate bed environment for sleeping (to reduce mechanical vibration from floor)
Springs and dampers are the classic method to reduce vibration, but don't expect the solution to be easy. Vibrations is a 4000 level ME course.
If the problem is just the floor, then hanging the bed ...
- 7,148
1
vote
How to calculate the density of foam required to cushion impacts?
Its more the noise of the entire floor resonating with your jogging rhythm and vibrating as an echobox.
Even if you manage to soften half of the impact by a clever system of plywood and foam you delay ...
- 22.8k
1
vote
Microphone angled waterproofing
Why have the hole perpendicular to the front surface?
Angle the hole so that it is slightly uphill when the screen is at the angle as shown.
Or, could you fit a membrane on the surface of the ...
- 16k
1
vote
How can you maximize air flow through a sound maze in a HVAC transfer grille?
Yes, it is definitely going to impede the circulation of air. The fan of the HVAC blows the air very gently, so much so that for a large room one register maybe not enough.
For blocking the light you ...
- 22.8k
1
vote
What can be the reason of the constant 50 Hz sound in my home?
Indeed, if the spectral content of the noise is peaked at the mains frequency, it is evidence of a motor somewhere in the building that runs all the time. This could be a ventilator or exhaust fan for ...
- 15.3k
Only top scored, non community-wiki answers of a minimum length are eligible