Kenny G wrote on 08/17/16 at 20:42:45:


I am certain that 2 x 100 does not make 200 when it comes to sound.  The db scale is arranged so that every 10db increase is a doubling of loudness to the human ear.  When you go from 100 db t 110 db, the sound intensity is doubled.!


I tried to GOOGLE this question about 2 horns being twice as loud as 1....and I couldn't find anything.  I believe the reason is that the 2 horns will never have the pressure waves synchronized - so the intensity of the loudness will change as the pressure waves comes in and out of phase.

So the result is that 2 horns of equal power are only twice as loud if they are synchronized so that the pressure waves are in phase and the horns create a simultaneously larger pressure wave.  Most "dual" horns are made intentionally with different frequencies, this allows the horns to come in and out of phase, and the pressure waves change from being in and out of phase continually....and when they are in phase the combination makes the pressure waves stronger and at other times tends to cancel each other.  This pulsing effect does makes the sound more noticeable, and the pulsing may not be audible as it is most likely faster than the ear/brain can process (the same way you can't see the 60 cycle pulse that occurs in florescent bulbs or a cathode ray TV screen).

So...2 horns are louder than 1 - but I am not sure they are twice as loud (and it is maybe impossible for the human ear to be an accurate measure of the "loudness" of a sound from the "fullness" of a sound).