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The sample frequency was chosen so that it was more than twice the note frequency, so that the signal could be completely recovered from this sample.
 
The sample frequency was chosen so that it was more than twice the note frequency, so that the signal could be completely recovered from this sample.
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:<span style="color:green">Instructor's comments: Did you actually try it in MATLAB? Did it work? -pm </span>
 
===Answer 2===
 
===Answer 2===
 
Write it here.
 
Write it here.

Revision as of 06:58, 4 September 2011

Sampling of an A 440

Explain how one can use MATLAB to play an A 440. Discuss your choice of sampling rate. (Feel free to post a sound file of your output.)


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Answer 1

The signal we want is $ x(t) = cos(440 * 2\pi) $.

We can first create a vector of sample times. In this case, we'll let the sample frequency be 1320 Hz over a sample interval of [0,1]

t = 0:(1/1320):1;

Next, we can generate the sound samples vector from the sample times vector.

y = cos(440*2*pi*t);

Finally, we play the signal by using the "sound" command, which needs the user to specify the sound vector and the sample rate of that vector. Our sample was 1320.

sound(y, 1320);

The sample frequency was chosen so that it was more than twice the note frequency, so that the signal could be completely recovered from this sample.

Instructor's comments: Did you actually try it in MATLAB? Did it work? -pm

Answer 2

Write it here.

Answer 3

write it here.


Back to ECE438 Fall 2011 Prof. Boutin

Alumni Liaison

Ph.D. 2007, working on developing cool imaging technologies for digital cameras, camera phones, and video surveillance cameras.

Buyue Zhang