Why do I hear nothing? sound function

I finally wanna hear what a linear function sounds like. Why does:

dt = 0.001;
t = 0:dt:2;
x = 1.*t;
plot(t,x)
sound(x,1/dt)

not work? Too low frequency? Or is it a property of the function, because there are no oscillations in it?

Answer 1

[Adam Danz]

According to the documentation, the sound data (first input to sound()) is an mx1 or mx2 matrix. Your sound data are 1x2001. Sound data typically contains values between [-1,1]. The range of your sound data is [0,2].

Valid sampling rates (second input to sound()), are 1000-384000Hz, accepted by Matlab, but also depend on your hardware. In reality, 1000Hz is very low for standard hardware. My Realtek audio supports a 44.1k/48k/96k/192kHz sample rate. To see info on your audio card in Windows, run dxdiag (win + r), and look at the Sound tab.

If you run your audio without specifying the sampling rate or specifying a much higher rate such as 44100, you should hear two clicks.

sound(x'-1, 44100)

1. transposed to conform to the expected inputs (a column vector)
2. -1 to conform to the typical range of audio data

More info on playing sounds in matlab.