> David, how do you select the parameters for generating the spectrum? I've=
found that depending on the parameters, especially the window size, the re=
sulting spectrum can look very different. I assume one wants a larger windo=
w size for lower frequencies, and vice versa, but how large? (I use Audacit=
y too.)
Peter,
A window size is the number of samples used for the fourier analysis of
frequencies. Generally the more samples, the more accurate the frequency
data, but the more blurred the time data.
I'm still on V1.3 beta on this laptop but the Analyse - Plot Spectrum
settings are:
Algorithm: spectrum
Function: Hanning
Size: 16384 (also use smaller for shorter sound selections)
Axis: Log frequency
You can resize the window both ways by dragging
For quiet passages like noise, select a section and Effect - Normalize
first, remembering to CTRL-Z cancel afterwards.
I find peak frequencies on the cursor are not always accurate.
With spectrograms, (Edit - Preferences - Spectrograms) I start with
Window size 4096, Frequency 0 to 20000, Gain 30 Range 60
Dragging over the frequency column selects a range, reset by right clicking
A smaller window size gives more accurate time info but less accurate
frequency data.
Does that help?
David Brinicombe
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