SPL computation, Prms computation
According to "Engineering Acoustics" and "Engineering Noise Control"(Bies and Hansen), which was referenced by Wikipedia as well http://en.wikipedia.org/wiki/Sound_pressure
To do this
20 log (pRMS/pRef)
where pRef is the reference sound pressure and pRMS is the rms sound pressure being measured.
Does "pRMS" mean that I don't use the "samples-turned-into-pressure" values directly? That I have to get a sequence of the values(discrete time system), get the RMS of that sequence and then use it as an input to the above formula? If so, then how many "samples" should I get in each RMS computation?