# RS SPL Meter Accuracy



## dguillor (Sep 19, 2014)

The spec sheet for the meter shows +/-2dB accuracy. Is that correct? That doesn't seem great. I don't see a mention of a cal file or curve.

Thanks.


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## Wayne A. Pflughaupt (Apr 13, 2006)

It’s actually worse than that. No calibration file is needed because SPL meters, especially cheap ones, are designed to measure noise levels, not frequency response. Believe it or not, accurate SPL meters don’t come cheap. Meters accurate to +/- 1 dB can cost hundreds of dollars.

Regards,
Wayne


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## JohnM (Apr 11, 2006)

Note that there are two kinds of inaccuracy to consider. The one the meter specs are stating is the absolute accuracy of the SPL reading they produce, the main classifications are class 1 (+/- 1 dB) and class 2 (+/- 2 dB). For our purposes, the frequency response also needs attention, the meter specs don't have much to say about that. There is a generic frequency response cal file for the RS meter in the downloads section, but above a few kHz there is a peak of several dB which varies in position meter to meter, and a rapid roll-off after that, so they are no good for full range measurements.


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## dguillor (Sep 19, 2014)

Thanks for the information, and I think I understand SPL meters better now. I am going to use a calibrated measurement mic for REW.


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