Originally Posted by Bill Fitzmaurice
Laboratory grade meters aside it's as good as any and better than most. Its accuracy is a lot better than your ears. As with any 'C' weighted meter you do have to use correction factors below 50Hz.
It's highly inaccurate at high frequencies as well. I've tested it against a basic behringer mic and it has a clear resonance probably caused by the plastic enclosure.
I agree that's its good enough and better than your ears, but the reason people use it is not to get an absolute measurement of 85dB, but more typically a relative measurement of the individual SPL levels of each channel. For this purpose it is well suited. Apparently the accuracy overall is +/-2dB so its not designed to be exact.
So don't freak out over exactly getting test tones to any particular reference standard. What you are caring about is channel balance. For that you are best off just using the volume level you use on your receiver the most. Baseline a speaker. From there, regardless of what that speaker measured, adjust the other speakers to that value.
So. if you measured 82dB, then from there on calibrate each speaker to 82dB.Edited by Sdiver2489 - 7/11/12 at 6:56am