Re: GB vs MB - a proposal
Kees-Jan Dijkzeul (keesjan@win.tue.nl)
Mon, 23 Dec 1996 10:11:46 +0100 (MET)
Neil Moore:
>
>
>> On Tue, 17 Dec 1996, Neil Moore wrote:
>> > Especially when considering that bels are measured exponentially.
>> > 1 MB is 1E100000 times as loud as 100dB, which is approximately
>> > the human pain threshold.
>>
>> Is that logarithmic or exponential? I don't remember. In any case, I
>> wonder how much damage a 1 MB sound would cause if let loose on the
>> surface of the Earth in the middle of, say, downtown Washington D.C. or
>> Los Angelas :)
>
>It is exponential. Logarithmic functions have decreasing slopes,
>exponential functions have increasing slopes.
I'm sure you've got this right in you mind, but still it's logarithmic.
Intensity of sound is usually measured in Watts per square meter. To arrive
at dB's you take the log of this and multply by 20 (or something like that)
That's why deciBells have a so-called logarithmic scale.
Of course, to convert back to W/m^2 you have to divide by 20 and
exponentiate.
Of course all this is somewhat irrelevant since we experience sound
intensity logarithmic. i.e. twice as much decibells will (in our experience)
sound twice as loud. That's why they've come up with it in the first place.
Groetjes, (dutch greetings)
Kees-Jan