Estimating Exhaust Sound Levels

[vex]

Originally Posted by Monkman33

80db would be about 25% of the volume to the human ear as 100db. technically speaking, an increase of 3db is doubling the acoustic output, but it takes about a 10db increase to double the volume perceived by the human ear.

At least, this is my rudimentary understanding of the concept.

Maybe I'm misunderstanding you. Are you saying that a reduction of 1/5 of measured db equates to about a 1/4 reduction in perceived loudness of the individual?

I understand that human hearing is logarithmic in nature (able to differentiate volume of quiet noises effectively while differentiation of loud noises is harder), but I'm not sure I quite follow your statement.

[j9fd3s]

Originally Posted by vex

Maybe I'm misunderstanding you. Are you saying that a reduction of 1/5 of measured db equates to about a 1/4 reduction in perceived loudness of the individual?

I understand that human hearing is logarithmic in nature (able to differentiate volume of quiet noises effectively while differentiation of loud noises is harder), but I'm not sure I quite follow your statement.

the DB scale is logarithmic. not that guitar amps or amps in general are rated consistently, but if i had a 50 watt guitar amp and a 100 watt amp right next to it, A you'd be deaf for a week, and B you'd be able to tell which one was which, but barely.

there are also a few frequency's that the human ear hears better than others.

AND the sound waves are affected by the medium they are going thru, so even the weather matters, somewhat.

BTW i have a copy of a road test of racing beat's IMSA gtu car from 1980, and they measured 133DB@50 feet. i have stood 50 feet away from the factory 79 imsa car (the green one at the top), when they are warming it up, and its so loud you can't really hear it

mike