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 ...
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4
votes
How do I remove outliers in measured sound pressure levels data?
What you are asking is not trivial. As PeteW said, you probably will find something in DSP, although this might be a bit too basic for them.
The problem with sound measurements is that the amplitude ...
- 24.3k
4
votes
Accepted
Why does the frequency of a bottle filling up changes?
Most acoustic vibrations of air more or less confined to a given geometry can be explained by two basic models. One is the one-dimensional treatment of the air in a tube, and the other is the lumped-...
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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
3
votes
Accepted
How to identify the source of low frequency noise from the street?
Several important clues here, as follows.
First we note the very strong 50Hz spike. I will assume from the spelling of your name that you live in a place with 50Hz AC mains. Many different types of ...
- 15.3k
3
votes
Can two microphones placed within centimeter distance together measure a distance of the sound source?
A sound source and listening device can only provide direction.
Multiple microphones is how passive submarine sonar works. This will give direction only. Note that microphones in a line can only ...
- 7,148
3
votes
Why does the frequency of a bottle filling up changes?
The frequency of the sound you're hearing is related to the changing resonant frequency of your bottle based on the frequency/velocity relationship of sound waves ...
- 2,357
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
2
votes
Accepted
Confusion over textbook formulae for directional characteristics of sound sources
The sound pressure does go negative, that is out of phase with the reference signal.
Incidentally your plot is confusing to me, as x axis seems to be either frequency or wavelength(?), so you are ...
- 912
2
votes
What is the mechano-acoustic effect of off-centering the black paste on tabla-drum skins?
Simply put, the blobs of paste act to damp out any vibrational modes which would have had mode maxima at that physical location. The energy applied to the drum then goes into other modes, presumably ...
- 4,259
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
IC engine Exhaust gases flow simulation through absorption type muffler
Fiberglass or some other sound-absorbing material surrounds a straight pipe in an absorption muffler. These are typically called glass packs in the US. The straight pipe is perforated, and the sound ...
- 7,148
1
vote
High voltage wires
Yes, they'll be noisy during rain, and even when it is misty or just humid out. It'll make a humming crackling sound.
I'm not touching the question about ionization and cancer with a barge pole. The ...
- 2,767
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 ...
- 912
1
vote
Materials that will block water but allow sound to travel through without being muffled
The easy solution is as follows.
Get you the cheap, thin white trashbags as used to line kitchen wastebaskets. This material will attenuate sound very little.
Now note that what attenuation there will ...
- 15.3k
1
vote
Can two microphones placed within centimeter distance together measure a distance of the sound source?
If the distance you want to measure is small than maybe you can use one of the microphone as a sound source.
But using a active sound emitter would be a better option.
1
vote
How do I remove outliers in measured sound pressure levels data?
If the data is over a 24h period and you have the times of these "other" sources causing the outliers then you can exclude those times from the general analysis.
Deleting those time entries ...
- 16k
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