Quote:
Originally Posted by LIforrelaxin
So as I started to spread some facts into this discussion yesterday I though I would finish today... I did a little more looking around to day and found the information I was looking for related to the fly by sound reading and it basis at 50 feet... what I found was this... for a given distance if you increase your distance by that same amount away from a given noise source you decrease the source level by 6 db... hence at 50 ft... you can calculate a 12 db loss at 150 ft. And with the 150 ft rule no boat should be operating at speed closer then 150 feet from you.
Now with a 82 db requirement on a fly by pass at 50 feet... you can see that at 150 feet the sound should be down to 70 db at 150 ft.... Mathematically speaking of course.... now from my previous post... that puts us at the same db level as a normal conversation between two adults doesn't it... hummm even quieter then the traffic in Meredith on the weekends for all that matters....
Now on to some other points here... we are talking about db... sound pressure folks... its what causes the damage... to the ear drums... now how loud something appears is a different story all together, and depends on many many factors... such as... distance, dampening material between you and the device... room for echo.... other ambient noises at the time, etc. etc.....
These folks are the facts of the situation.... If a boat is legal... there is nothing to complain about... Because if you complain about the noise of the boats... you better complain, about the traffic in Meredith, your conversations in your yard... The vacuum cleaner, and your radio.... most people listen to their radio at a db level of around 70 - 80 dbs.....
So here is the deal... There is a existing law... it is sound in more then one way according to everything I can find... If you feel someone has a boat that doesn't conform to the law, talk to the Marine Patrol, they will investigate. Just remember the next time your out on your dock talking in the boat... your neighbor just down the shore front may call the police on you for making to much noise.
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Here's another factor that most people are not aware of, even as a HONDA CIVIC comes tooling up the street toward you... (Actually it's a
Self Propelled Sub Woofer.) The
Doppler Effect makes sound measurement even more difficult to reliably deal with.
NB
http://en.wikipedia.org/wiki/Doppler_Effect