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The physics of sound?

  1. Jun 29, 2013 #1
    I've been trying to teach myself the physics of sound. Specifically ive been trying to find out the variables that make up the human voice- the entirety of what separates one voice from another.

    But after browsing through one too many overly technical wikipedia articles, and finding one two many sites that only scratches the surface of how sound works, i'm at a loss.

    Could anyone recommend a text theyve had an experience with, or another source of learning?

    Would be greatly appreciated! :)
  2. jcsd
  3. Jun 29, 2013 #2

    Simon Bridge

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    voices are very complex - you will need to build up your ideas about how sound works slowly, a bit at a time.
    Any standard freshman college text will give you the basics - develop from there.

    The human voice requires understanding interference and diffraction wrt the changing geometries of the different elements of the human vocal apparatus. Everything from the chest-cavity, lungs, diaphragm, vocal chords, ear-voice feedback and so on. Just the shape of the mouth changes the voice, so does the air pressure through the vocal chords, position of the toungue ... see what a project you have set yourself?

    But you can simplify the process by figuring what you want to use the final understanding for.
  4. Jun 29, 2013 #3
    Here's a fun little video showing among other things how the human voice can be visualized through a spectrum analysis. You get to learn a little about the FFT and oscilloscopes along the way.

  5. Jun 29, 2013 #4
    Sounds exciting! And it definitely sounds like there's lots of material to keep me busy. It's reassuring that it's expected to take me some time to work up to, because i wasnt sure if my confusion was justified or not.

    Thanks for the help!
  6. Jun 29, 2013 #5
    Really cool resource! Thanks for the tip!
  7. Jun 29, 2013 #6
    That's what I'm here for, mpatryluk :wink:
  8. Jun 29, 2013 #7

    Simon Bridge

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    I remember a teaching demo where I showed, on an oscilloscope, how different musical instruments have different sounds even when playing the same note and tried it with voices ... and discovered a student with perfect pitch. Watching the jagged voice waveform settle into a sine wave was creepy.

    Anyway - a good first step is to see if you can work out how different instruments get different sounds.
    Pick instruments that have basically the same way of making the sound but still sound different playing the same note. Keep things as much the same as you can without actually having the same instrument and keep it simple so you can build the instruments yourself.

    Good luck and have fun.
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