Beach123456
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Quote:
I think he meant if you stand in the same place to measure it. As in speakers 1/8" from your ear measured from 1/8" away. Then measure from 32' away and turn it up until it is back at 140. You have to keep it at 140 for what he said to be true.
Originally Posted by loopsider I don't think that is true...inverse square law? Distance makes a huge difference! 140 db SPL at 30 ft loses intensity over those 30 ft. 1/8th'' pretty much retains 100% intensity. Lets do the math (please correct me if I am wrong, because I most likely am...I have percieved from articles that the dB decrease is a linear function while the distance is exponential): 1/8''=140 db (which is, by the way, EXTREMELY loud) 1/4'' = 134 db 1/2'' = 128 db and so forth, until we achieve 30 ft... ------------------ 21 1/3 ' = 74 32 ' = 71 db? This is possibly correct, please say if I am not. Whatever the case, it stands that sound reduces intensity through distance. |
I think he meant if you stand in the same place to measure it. As in speakers 1/8" from your ear measured from 1/8" away. Then measure from 32' away and turn it up until it is back at 140. You have to keep it at 140 for what he said to be true.