In a project where I study sounds, I use the Audacity spectrum analyzer.
I am willing to match the 0 dB reference with a real measurement made with an SPL meter.
So far I only worked with Audacity:
- I generate a white noise track with amplitude 0 dB.
- I use the spectrum analyzer and export the data.
- I import the data in Excel and compute the signal dB by “adding” all the bins dB level. (adding dB the correct way = 10*log(10^(L1/10) +…+ 10^(Ln/10))).
Result: I get something close to 0 (usually 1 - 3 dB off) but not zero. The result depends on the function (FFT window type).
I guess this is normal but I would like to know which function is the best to have accurate peak amplitude and total dB level.
Thanks for your help.