Post by Pat on Oct 19, 2008 8:41:18 GMT -6
I just got done watching one of the most misleading and idiotic pieces of reporting pap I have seen in a while. A reporter at WMBF News (see story at www.wmbfnews.com/global/story.asp?s=9200476) goes to Radio Shack, buys himself a sound meter, and then goes to the car show thinking he is now Albert Einstein. He then vaguely waves this thing around open engine compartments and concludes that show cars will pass Myrtle Beach's noise ordinance with no problems.
Only thing is, what he did is not even close to how the actual sound tests are performed on bikes per the SAE J1287 standard. WHat he SHOULD have done, among other things too numerous to mention, is place the meter 20 inches away from the vehicle exhaust at ground level and at an angle of 45 degrees from the centerline. Had he done that, our roving reporter who was pretending to know what he was doing but did not would have found sound levels FAR higher than with what he did. And yet his report implies the exact opposite. The key concept is that the sound level of something depends CRITICALLY on where and how you measure it. If you are going to make a comparison between two sound sources, you have to measure them the same way or the comparison is invalid. And since sound levels drop off as the square of the distance, if you are farther away from the noise source (the exhaust pipes) in one versus the other, you will get dramatically reduced levels.
In fairness, they did note the report was "non-scientific", but a more accurate description would have been "completely bogus." This is how we end up with bad laws. People who don't know what they are doing just kind of make it up (like this reporter did and like apparently the city council did) and hope that no one calls them out on it.
This whole topic is nowhere near my area of expertise, but if I can educate myself on it in a relatively short period of time, so could have the Mayor, the City Council, or our WMBF reporter friend who should have studied more in science class. But why expend the time and energy to know what you are saying when there is no apparent penalty for BS'ing your way through life.
And THAT, dear reader, is my pet peeve for today.
Only thing is, what he did is not even close to how the actual sound tests are performed on bikes per the SAE J1287 standard. WHat he SHOULD have done, among other things too numerous to mention, is place the meter 20 inches away from the vehicle exhaust at ground level and at an angle of 45 degrees from the centerline. Had he done that, our roving reporter who was pretending to know what he was doing but did not would have found sound levels FAR higher than with what he did. And yet his report implies the exact opposite. The key concept is that the sound level of something depends CRITICALLY on where and how you measure it. If you are going to make a comparison between two sound sources, you have to measure them the same way or the comparison is invalid. And since sound levels drop off as the square of the distance, if you are farther away from the noise source (the exhaust pipes) in one versus the other, you will get dramatically reduced levels.
In fairness, they did note the report was "non-scientific", but a more accurate description would have been "completely bogus." This is how we end up with bad laws. People who don't know what they are doing just kind of make it up (like this reporter did and like apparently the city council did) and hope that no one calls them out on it.
This whole topic is nowhere near my area of expertise, but if I can educate myself on it in a relatively short period of time, so could have the Mayor, the City Council, or our WMBF reporter friend who should have studied more in science class. But why expend the time and energy to know what you are saying when there is no apparent penalty for BS'ing your way through life.
And THAT, dear reader, is my pet peeve for today.