I explained how it is done, there is no calculation on an axis. This is done with a noise level monitoring device, which almost works like having a source microphone of an old tape recorder withnachthexe wrote:An increase of 10 db is twice as loud, no matter what type of sound! I wrote this based on the presented numbers, I do not know how they were measured or obtained. they might be incorrect, But I can only go based on the posted values.gas56 wrote:nachthexe wrote:
Not in measuring the sound level of firearms. There would be no way to calculate noise level unless 1st you had somewhere to start with the sound factor number with a set distance.
The loudness of the db meter was taken at a very close range, around a few feet. and around 100 yards away it will read around 60% loss on the scale. How do I know this? Where I live noise disturbance from a firearm being shot off has to be measured with a sound reading device at 93 db or lower to your closest neighbor which in my case was 100 yards to just on the other side of the road to my shooting range. And no matter how much they complained the law is the law as the noise level was @ 91.6 db with a .357 magnum handgun at that range. I never measured it from 5 feet away so I don't know the sound level from that gun, but the db above for the .357 seems pretty close with around 60% loss. All I know is that you want to wear your ear plugs at that close distance unless you want your ears to ring for awhile.
Vu meters which gives you the numbers of the readout which are set/calibrated at minus/plus zero db from a distance of 5 feet.