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Resonance in a Bathroom Stall

  1. Sep 25, 2007 #1
    The other day, I was in a bathroom stall doing my business, and I randomly started humming some song (can't remember exactly what it was). Well it just so happened that I hit the resonant frequency of that stall. Talk about a surprise! I could make a very quite sound with my mouth closed, and if I hit just the right frequency the stall practically started throbbing. Just the very quite vibration of my throat would make the stall utter a loud hum. I was just wondering if anyone else has ever noticed this. I have plans for future tests. I'm going to build some kind of audio generator that I can adjust the frequency of until I hit resonance, and see if I can knock the stall down. :smile: Anyway the next time you get a chance try this. I'm sure you and the person in the next stall will get a kick out of it.
  2. jcsd
  3. Sep 25, 2007 #2


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    these are called room modes and they are most prevalent in rectangular shaped rooms with smooth and hard surfaces. you can predict what frequencies are the room modes. when i get back to this, i'll post the equations or point to a web site with it. try Googling "room mode" or "room modes".
  4. Sep 25, 2007 #3


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    Just don't make any hand signals under the divider or tap him on the foot. :rofl:
  5. Sep 25, 2007 #4
    Tesla claimed to have created an earthquake machine that vibrated at a rooms resonant frequency. He claimed to have destroyed his lab and caused results from the fire department.

    Incidentally, all of his neighbors believed it was an earthquake.

    Please tell me how ur attempt at knocking down the stall goes :rofl:.
    Last edited: Sep 25, 2007
  6. Sep 25, 2007 #5


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    I once noticed the same thing about a hallway in the huose ni which I grew up. If I clapped my hands, it sent back several diffeernt pitches. If I listened carefully to those pitches, selected one, and hummed it, the hallway would hum back with just that one pitch. At other notes, the place sounded completely dead.

    Bedframes are good for this, also.
  7. Sep 25, 2007 #6
    The distinguished Gentleman has just entered the chamber.
  8. Sep 25, 2007 #7
    A while back when I used to inspect large 20,000L stainless steel chemical storage/hauling containers. I would go in and do an internal inpection and while I was at it, if I hit just the right hum in my throat it would be deafening with very little use of my vocal cords at all.

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