"Bill Gill" wrote in message ...

On 4/2/2014 8:38 AM, Phil Allison wrote:
"Bill Gill"

It takes ten times the power to seem twice as loud.

Ten times the power is 10 dB, that is 10 times as loud.

** ********.

Most would say it was 2 or maybe 3 times as loud.


Twice as loud would be 3 dB.


** ******** again.

+3dB is only slightly louder.

+1dB is almost unnoticeable.


.... Phil


In one respect you are right +1 dB is just detectable. That is
how it was originally defined. +3dB is twice the power. To my
mind that is twice as loud. +10 dB is 10 times the power. Again
that would be 10 times as loud. Check the math. The calculation
is 10 * log(10) P2/P1.

Bill



"Twice as loud" usually refers to how the human brain perceives how loud the
sound is. It is nothing much to do with mathematics, but just how our
auditory systems work.

It turns out that the average person thinks a 10dB increase sounds about
"twice as loud".


I'm not really sure I could determine at what point a sound was twice as
loud as previously, it seems far too arbritary and subjective an assumption
to me.
If not totally meaningless.



Gareth.