Correct Plot of FFT Phase for Audio File Analysis?

[JJ91]

Homework Statement

I would like get an advice whatever the plot of phase (in radians) of the FFT computation of audio file is correct.

Is it not supposed to show a decrease as the frequency increases ?

Homework Equations

 

[mfb]

Phase relative to what? And why does it go from -2500 to +8500 and not from -pi to pi?
Where does the signal come from, why do you expect some specific phase?

 

[JJ91]

Phase relative to what?
Relative to amplitude at specified frequencies

And why does it go from -2500 to +8500 and not from -pi to pi?
The command used unwrap() was supposed to make a range of -pi to +pi, however in MatLab it just doesn't work thus I assume it means -2500 rad to +8500 rad.

Where does the signal come from, why do you expect some specific phase?
The signal comes from the FFT of file audio.wav, I had no idea what I was expecting for "phase" the amplitude however makes clear sense.

 

[mfb]

Relative to amplitude at specified frequencies

I don't think this makes sense.

however in MatLab it just doesn't work thus I assume it means -2500 rad to +8500 rad.

Well, where is the difference between a phase of x and x+2n*pi?

I had no idea what I was expecting for "phase"

Me neither, so why do you care about the phase?

 

[JJ91]

It was part of the question for analysis of an audio file. I end up submitting only amplitude component, the graph waveform however was correct, the range wasn't.