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The Clarinet

  1. Aug 4, 2006 #1
    As a clarinet student, i have always been told two things:

    1.) to change your loudness, change the amount of air you send through the horn, not the speed at which you send air through it. if you change the speed, you will change the pitch.

    1.) you can change your pitch by tightening or loosening your embochure (the way your mouth grasps the mouthpiece)

    after learning about sound in physics, im a bit confused about wuts going on.

    if you blow air faster through the horn, do you increase the speed of sound since the medium through which it is propogating is in motion as well?

    since the area of the opening of the mouthpiece doesnt change, to "send more air through the horn," wouldnt you HAVE to increase the speed of the air?

    how does the embochure effect the speed of the air?
  2. jcsd
  3. Aug 5, 2006 #2


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    Was a musician myself in highschool, and was told the same things.

    Yes, you have to send air through the intsrument faster to get more air through the same volume of spac in the same amount of time.

    The embochure doesn't effect the speed of the air very much, but it does effect the speed at which the reed (or your lips, for a brass instrument) will vibrate. This gives you your change of pitch.
  4. Aug 5, 2006 #3
    Another interesting thing about such an instrument is that one can change the outcome by changing the shape of ones mouth.
  5. Aug 5, 2006 #4


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    There's another bottleneck -- all of the air you blow has to go through the tiny hole between the tip of your reed and the mouthpiece, and that opening changes size quite a bit!

    But it could just be psychology -- I did some testing here at my desk. When I thought "I want to blow lots of air", I breathed with my diaphragm, and my mouth/cheeks were fairly controlled. When I thought "I want to blow air fast", I breathed with my mouth, and my mouth/cheeks were fairly uncontrolled. (In fact, my cheeks puffed out)

    I also tested on the recorder I have handy -- when I thought "I want to blow fast", I breathed differently than when I thought "I want to play loud"... and blowing fast was, in fact, sharp.

    (I didn't want to put my clarinet together for testing)

    I'm not sure... but doesn't your mouth also act as part of the resonating cavity?
  6. Aug 5, 2006 #5


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    Loundess of a sound comes from how much air is being moved pretty much. dB measure "sound pressure."

    I believe that would be affect.
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