Thread Tools
Old 12-08-2007, 03:23 PM
Guest
Join Date: Jun 2001
Posts: 19,717
How loud is 20 dBA?

How loud is 20 dBA?

-FrL-
Old 12-08-2007, 03:26 PM
Arms of Steel, Leg of Jello
Charter Member
Join Date: Nov 2000
Location: Riding my handcycle
Posts: 34,702
Decibel levels.

Rather quiet.
Old 12-08-2007, 03:27 PM
Charter Member
Join Date: Jan 2003
Location: Richmond, VA
Posts: 22,536
About this loud.

20 dB is pretty quiet. It's about the level of background noise you'd expect in typical library during off-peak hours.
Old 12-08-2007, 03:28 PM
Guest
Join Date: Mar 2006
Location: Southern North
Posts: 1,383
This link compares it to rustling leaves.
Old 12-08-2007, 04:00 PM
Guest
Join Date: May 2000
Location: Brooklyn
Posts: 23,861
It's roughly as loud as This guy's shirt.
Old 12-08-2007, 05:27 PM
Charter Member
Join Date: Sep 2003
Location: Southeast Florida USA
Posts: 21,035
Make sure you're understanding whether you're talking about a sound of loudness = 20dBA or whether you're talking about two sounds whose loudness difference = 20dBA. Since the scale is logarithmic, that can make a huge difference.
Old 12-08-2007, 06:53 PM
Guest
Join Date: Mar 1999
Location: Scania
Posts: 4,917
Actually, dB comparison tables aside, 20 dB is almost impossible to experience in any normal environment You're going to have to get in a really isolated sound chamber, because background noise at just about anywhere is above 20 dB
Baffle cited a table saying rustling of leaves But if they rustle in nature, there's wind, and that alone will be louder than 20 dB.

Now, if this question is qabout dB levels of computer fans, and if it's worth the money to get a 12 dB fan, as opposed to a 20 dB fan, then the answer is yes. Even though the fridge @ 40 dB and the computer fan @ 20 dB doesn't equal 60 dB background noise things tend to add up. All in all, it depends on the room you're in.
Old 12-08-2007, 07:51 PM
Charter Member
Join Date: Jan 2003
Location: Saskaboom
Posts: 8,967
Quote:
Originally Posted by Charlie Tan
Now, if this question is about dB levels of computer fans
If this is a question about dB levels of computer fans, the OP should note that the noise ratings are often completely unreliable. Some fan manufacturers make completely unrealistic claims about the noise levels of their fans. If a fan is actually at 12dBA @ 1m, chances are extremely good that it's not running.

If you're serious about making a computer quiet, the place to go is silentpcreview.com.
Old 12-09-2007, 04:18 AM
Guest
Join Date: Aug 2001
Location: Japan
Posts: 2,964
Quote:
Originally Posted by Q.E.D.
20 dB is pretty quiet. It's about the level of background noise you'd expect in typical library during off-peak hours.
That's very, very optimistic. In our recording studio control room, the background noise is about 30dB. This is a rather typical, if slightly high, value. It is nevertheless very, very quiet. The noise criterion standards give recomendations of 40 to 50 dBA for libraries and and 25 to 30 dBA for recording studios.

There is a difference between talking about ambient noise levels and the loudness of a particular source. If I say that my studio has a background noise level of 30 dB it means that if I stand somewhere in that room, the sound level is going to be at least 30 dB.

If I say that rustling leaves are about 20 dB, it means in practice... nothing. A jet taking off is 20 dB, and so is a gun going off, and the Krakatoa eruption... at the right distance. A noise measurement for a point source without a distance has no practical meaning, inverse square law and all.

Last edited by jovan; 12-09-2007 at 04:19 AM.
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 11:34 AM.

Send questions for Cecil Adams to: [email protected]

Send comments about this website to:

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Copyright 2018 STM Reader, LLC.

Copyright © 2017
Best Topics: nonconductive metal sight puns funny rhymes dirty multiplication wheel 4f draft dive pool depth dum dum ammo rid x liquid suck boobies sebastian nicknames frozen wart 1950s smoking how to mail checks long sleeve shirts under short sleeve shirts three dots in a row tattoo meaning what is the difference between economy and standard shipping solar fan for car mano y mano definition how many generations in 200 years five ways to sunday maynard g. krebbs tires that last forever why does iron cause constipation j on the periodic table family guy pot song fishing with wd 40 remove most visited sites from new tab