Which parameter of my audio file does Y refer to, where Y=wavread('sound.wav') ? Is it the volume or any other parameter?

I need the pitch contour plotted for two audio files. I used wavread() function but i am unsure which parameter of the audio data 'Y' represents. Kindly guide me.

I need to compare the pitches of two audio files.

Answer 1

[Walter Roberson]

Y represents amplitude, probably in the scale -1 <= Y < 1 .

[Jan]

@Walter: This answer is absolutely clear on first sight. But which amplitude is this exactly? The mean over the time of 1/Freq of the voltage measured by the AD converter? Does it linearly depend on pressure at the membrane of the microphone?

[Walter Roberson]

No volts are necessarily harmed in the creation of the file. Could be on any arbitrary scale, created by any arbitrary process. Recordings of water levels over an aeon for example.