# calculate SPL-Third octave using poctave function

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zein on 24 Jun 2020
Commented: zein on 17 Mar 2021
I want to calculate the sound pressure level third ooctave using poctave function
I used poctave function to convert pressure data (p) (time,pressure) to 1/3 octave spectrum
[P3rd, cf] = poctave(p,fs,'FrequencyLimits',[df,fs/2],'BandsPerOctave',3);
In order to calculate the SPL-1/3 Octave (sploct)
sploct = 10*log10(P3rd/pref^2);
Is the equation for calculating SPL-1/3 octave is correct or not?
Urmila Rajpurohith on 1 Jul 2020
The solution provided here (The question where you commented)solved your issue?

zein on 5 Mar 2021
Edited: zein on 5 Mar 2021
[splfiltb,fcfiltb] = filtbank(p,fs,[],'extended');
%using poctave fun
pref=2e-5;
[P3rd, fc1] = poctave(p,fs,'FrequencyLimits',[3,fs/2],'BandsPerOctave',3);
sploct1
= 10*log10(P3rd/pref^2);
I have used both these two methods (filtbank and poctave fun) and they showed the same resultsm check them
zein on 17 Mar 2021
send ??

ngoc quy hoang ngoc quy on 4 Mar 2021
do you have the answer? I am also interested in this question