[OT] Decibels and the ear [was: Re: [plug] Hot and bothered CPU hankers for cool breeze]

[Mike Holland]

On Wed, 17 Dec 2003, James Devenish wrote:

> wrote for his initial comment that 10dB ~= twice as loud :-) So, a
> nominal three decade increase from 399 extra machines could be perceived
> as eight times louder than one machine, which is the sort of thing I was
> wondering about. Sorry everyone!

Amongst the interesting technical comments, I think the simple answer was
lost. 400 fans are 400x louder.
  Its more sensible to humans to talk in dB, but then its wrong to speak
of multiples. 100dB is NOT double 50dB. Just as a temp of 20 deg.C is
not double 10C. (more like a 3% difference)
  It just doesnt make any sense to talk about multiples (e.g. doubling) on
an open-ended logarithmic scale with an arbitrarty zero point.