I have got some impulse response data that I would like to transform via Fourier
to get the amplitude-frequency characteristics of the performing loudspeaker. The final goal is to show (e.g. via ListDensityPlot
) how the calculated amplitude-frequency characteristics is dependant on the window I choose to transform (truncation of low frequencies). The issue I have is to get Fourier
to behave like desired - I am unable to reproduce the frequency response that I got out of another 3rd part software. The issue:
There is no SampleRate
option for Fourier
(and I got a sampling frequency of 48kHz)
The following example illustrates the issues:
data = Table[Sin[x], {x, 0, 100}];
ListPlot[
Take[10*Log10[(Abs@Fourier[data, FourierParameters -> {1, -1}])^2],
Floor@(Length[Fourier[data, FourierParameters -> {1, -1}]]/2)],
Joined -> True, PlotRange -> Full]
Periodogram[data, FourierParameters -> {1, -1}, SampleRate -> 1,
PlotRange -> Full, ScalingFunctions -> "dB"]
ScalingFunctions -> "Absolute"
, and compare against aListPlot
of theFourier
transform, notListLogPlot
. However, as posted, the two plots are identical except for their scale. $\endgroup$Fourier
. I will change the question accordingly. $\endgroup$ListLogPlot
appliesLog10
to the data and makes y-axis ticks in logarithmic style. ButdB
aren't justLog10
it's10*Log10
. And alsoSampleRate
needs to be changed to number of data points, 100 in your case. $\endgroup$Fourier
that. $\endgroup$