In Reply to: RE: ugh posted by Thorsten on July 14, 2012 at 10:46:17:
Thorsten babbles:
"Nope, the definition used in common acoustic texts is quite precise. It includes wavelength and radiation area for reasons that should be self explanatory."
Since there are many wavelengths involved, a definition based upon a specific wavelength is not useful or accurate. This definition is more useful and accurate in the context of a typical loudspeaker listening environment than anything you're likely to come up with that's based on the Fraunhofer definition of far field:
"The near field is the area very close to the machine where the sound pressure level may vary significantly with a small change in position. The area extends to a distance less than the wavelength of the lowest frequency emitted from the machine, or at less than twice the greatest dimension of the machine, whichever distance is the greater. Sound pressure measurements in this region should be avoided."
And it is commonly accepted in the industry and can be found here:
http://www.acousticvibration.com/sound-basis.htm
And it is exactly the same definition I used.
Now who is inventing what?
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Follow Ups
- double ugh - villastrangiato 11:48:57 07/14/12 (0)