about noise

[Guest]

Archived from groups: alt.comp.hardware.homebuilt (More info?)

Hi, supose you have 6 fans in your system: 1 for the CPU, 1 for the PSU, 1
for the NB,1 for the AGP, 1 for the HD and 1 for the case. Say, if all make
a noise of 30 dB, could we sum 30+30+30+30+30+30 = 180dB ?

180 dB is alot of noise dont you think?

Silva

 

[Guest]

Archived from groups: alt.comp.hardware.homebuilt (More info?)

On Mon, 19 Apr 2004 12:51:49 +0100, "Manuel Silva" <minasdomingos@sapo.pt>
wrote:

>Hi, supose you have 6 fans in your system: 1 for the CPU, 1 for the PSU, 1
>for the NB,1 for the AGP, 1 for the HD and 1 for the case. Say, if all make
>a noise of 30 dB, could we sum 30+30+30+30+30+30 = 180dB ?
>
>180 dB is alot of noise dont you think?
>
>Silva
>

No, noise is not additive. Do a Google search for relative loudness of
common sounds and you'll see that it's practically impossible to approach
180db with a computer, and if you did, you'd soon hear nothing at all, be
deaf.
http://www.howstuffworks.com/question124.htm

Further, there's no reason to use 30db fans. Highly o'c video card, CPU,
NB, case, can all be fitted with lower RPM quiet fans given properly
designed system with appropriate heatsinks and chassis design.

 

[Guest]

Archived from groups: alt.comp.hardware.homebuilt (More info?)

dB's are logrithmic; you don't just add them directly the way you did.

--
DaveW



"Manuel Silva" <minasdomingos@sapo.pt> wrote in message
news:4083bfd4$0$18451$a729d347@news.telepac.pt...
> Hi, supose you have 6 fans in your system: 1 for the CPU, 1 for the PSU, 1
> for the NB,1 for the AGP, 1 for the HD and 1 for the case. Say, if all
make
> a noise of 30 dB, could we sum 30+30+30+30+30+30 = 180dB ?
>
> 180 dB is alot of noise dont you think?
>
> Silva
>
>

 

[Guest]

Archived from groups: alt.comp.hardware.homebuilt (More info?)

Right. The situation Mauel describes essentially multiplies
the noise power by a factor of 6. The logarithm of 6 is
about 0.778, so you can add 7.78dB to the 30dB of a
single fan for your six fans.

*TimDaniels*


"DaveW" wrote:
> dB's are logrithmic; you don't just add them directly the way
> you did.
>
> "Manuel Silva" wrote:
> > Hi, supose you have 6 fans in your system: 1 for the CPU,
> > 1 for the PSU, 1for the NB,1 for the AGP, 1 for the HD
> > and 1 for the case. Say, if all make a noise of 30 dB, could
> > we sum 30+30+30+30+30+30 = 180dB ?