# Which smoothing filter to use in measurement



## sportflyer (May 2, 2010)

I have been using 1/48 smoothing filter in my Preferences. Should I use another smoothing filter like 1/6 instead ? What is the impact on using 1/6 vs 1/48 besides smoothing out the measured curve ? Tks


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## zheka (Jun 11, 2010)

sportflyer said:


> I have been using 1/48 smoothing filter in my Preferences. Should I use another smoothing filter like 1/6 instead ? What is the impact on using 1/6 vs 1/48 besides smoothing out the measured curve ? Tks


I am pretty sure that smoothing/averaging setting only affects the display, not the measurements.

I think the rule of thumb is to use very little or no smoothing for the low frequency graphs and heavier (1/6 or even 1/3) smoothing for full range graphs.

Ethan Winer of Real Traps recommends setting smoothing at 1/24 for LF and 1/3 for MF and HF range graphs
http://www.realtraps.com/art_measuring.htm


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## sportflyer (May 2, 2010)

Can the smoothing filters be applied after measurements?


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## zheka (Jun 11, 2010)

sportflyer said:


> Can the smoothing filters be applied after measurements?


yes. you can apply or remove smoothing for any existing measurements.


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## Phillips (Aug 12, 2011)

If you are using eq it pays to use the 1/3 smoothing so you don't over eq.
I generally use either 1/3 or 1/6


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

zheka said:


> I think the rule of thumb is to use very little or no smoothing for the low frequency graphs and heavier (1/6 or even 1/3) smoothing for full range graphs.
> 
> Ethan Winer of Real Traps recommends setting smoothing at 1/24 for LF and 1/3 for MF and HF range graphs
> http://www.realtraps.com/art_measuring.htm


Zheka has it right: No smoothing for low-freq graphs, 1/6 or 1/3 for full range. Due to comb filtering caused by reflections, most rooms deliver a “ragged” graph for the upper frequencies. Smoothing allows you to see the underlying trend in frequency response.

Regards, 
Wayne


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## sportflyer (May 2, 2010)

Wayne , you are right , the high freq graphs are raggedly without the smoothing filters. BTW when running the Sub curves should I leave the LPF of LFE at 120hz ? Would this setting would impact sub measurements in stereo mode ?


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