5 ms·
I was hoping for more science-y details. Any HN folks care to give a better explanation of what's going on here?
by jawns 14y ago
I was hoping for more science-y details. Any HN folks care to give a better explanation of what's going on here?
- dsr_ 14y agoThe room is anechoic and insulated. Anechoic means that the walls are treated to absorb all the sound waves that hit them, and not reflect them back. (Typically, anechoic surfaces are soft and cannot support much weight, so [guess] there is probably a support system to put weight bearing platforms inside.) Insulated means that sounds from outside the room are not transmitted in. A lot of concrete can take care of the high frequencies, but low frequencies often require special suspensions to keep sounds from the earth out. The most interesting thing is the measured extent of what they've produced.
- deleted 14y ago[deleted]
- ImprovedSilence 14y agoI've been in a few before. They are used a lot for testing the RF properties of wireless products. They basically let nothing from the outside in, and allow for no reflection on the inside. Thus you can isolate the characteristics of your device from any other possible surrounding noise. I usually get a headache after being in one for awhile, but I always assumed that's because the pointy foam shit smells like fresh paint.
- NewInstall 14y agoThe term is used for both RF and Audio wave absorbing rooms, but in this case they are talking explicitly about a room that doesn't reflect Sound.
- ImprovedSilence 14y agoWouldn't they be the same thing, just "tuned" to block out different frequency ranges? I'm guessing the tuning is based on the material and shape of the foam, and thickness and material of the walls? It's all waves.
- efraim 14y agoSound waves and radio waves are not the same thing.
- CamperBob2 14y agoThey're not the same things, no, but they obey the same wave mechanics, and due to the difference in propagation velocity, their wavelengths are actually very close. A wavelength of 3 meters is about 100 MHz in the RF world, and 1 kHz in audio terms. That's why an RF anechoic chamber looks a lot like an acoustical anechoic chamber, and often sounds like one too.
- Anechoic 14y agoA wavelength of 3 meters is about 100 MHz in the RF world, and 1 kHz in audio terms. An acoustic wavelength at STP is around 1ft/30cm, not 3m (which is closer to 100 Hz).
- CamperBob2 14y agoD'oh, you're right; I started punching calculator buttons with 1100 f/s and turned it into meters somehow. Point stands, though.
- Anechoic 14y agoIt's all waves. EM waves vs pressure waves, they're not the same thing (although the math is basically the same, just with different constants). Something that affects an EM wave won't necessarily affect a pressure wave - a Faraday cage for example will block EM waves but won't do anything to block sound waves.