# Question about Noise vs. Music

1. Nov 18, 2007

### NoiseQuestion

Hello everyone. I'm not a Physics major: I'm a Music major. And I have a question. I've read various books on acoustics, but I still haven't found the answer.

Ok. The way I see it, there are 2 basic types of sounds (I didn't get this out of a book, it's my own conclusion from everyday observation). One is pitch, the other is (for lack of a better word) noise.

Now every sound is a noise, right? True. But by pitch I mean a sound whose pitch we can determine. If I play a note on the piano, you can tell me "oh, that's a C", or you can give me some mathematical frequency for what we call "C".

By noise, I mean a sound whose pitch(es) cannot be determined. - And maybe I'm wrong about this, because I know next to nothing about Physics. But for example, say an airplane takes off and you have the unfortunate experience of standing behind it and you hear this EEEEEEEEEEEAAHHHHHHHHHHHH!!! or whatever. Now let's say you go to the piano and try to reproduce the "pitch(es)" of the engine going off. YOU CAN'T! Because the sound has no pitch we can determine. It's just noise.

Now here's my question. 1) Is everything I said above true? and 2) If it is, how do we describe, in scientific terms, what I have termed "noise?" If it has no defined pitch, what is it? What is the technical term for it, and how can we analyze it?

Last edited: Nov 18, 2007
2. Nov 20, 2007

### Staff: Mentor

Your definition of noise needs help. By your definition, human speech would be noise because it cannot be reproduced exactly on a musical instrument.

noise
technical definition
http://www.pcmag.com/encyclopedia_term/0,2542,t=Gaussian+noise&i=43682,00.asp

http://www.its.bldrdoc.gov/fs-1037/dir-024/_3556.htm

white noise
http://en.wikipedia.org/wiki/White_noise

brown noise
http://www.mediacollege.com/audio/noise/brown-noise.html