why are my speakers are srewing up my monitor?

Discussion in 'Macintosh Computers' started by phreakout13, Jun 12, 2004.

  1. phreakout13 macrumors 6502

    phreakout13

    Joined:
    Jan 4, 2004
    Location:
    South Eastern MA
    #1
    for some reason, when the built in speakers on my eMac are up loud, they make my display wiggly and such. At this point, the bottom left corner of my monitor is green. Naturally, I assume this is from the magnets in the speakers, but they always have to be up loud to hear. Why is this happening, and can I fix it? Thanks:)
     
  2. thehuncamunca macrumors 6502

    Joined:
    Jul 9, 2003
    Location:
    NJ
    #2
    it's the magnets in the speakers

    the only way to fix this is either to turn down the volume or get external speakers

     
  3. PowerMacMan macrumors 6502

    PowerMacMan

    Joined:
    Mar 17, 2004
    Location:
    Chicago, Illinois
    #3
    It's an eMac thing, get external speakers and they'll please you much more.
     
  4. Jigglelicious macrumors 6502

    Jigglelicious

    Joined:
    Apr 25, 2004
    Location:
    NYC
    #4
    Yep, get some external speakers. The ones inside the eMac sound horrible anyway, and the way they make the entire case resonate really freaks me out.
     
  5. King Cobra macrumors 603

    Joined:
    Mar 2, 2002
    #5
    A more technical explanation as to why that happens is as follows:

    Your eMac's flat CRT screen emits what you see with a certain refresh rate, such as 117Hz or 85Hz. Think of the emissions as monitor waves, although it's actually a very complex series of waves emitting different colors so many times per second. When you play sound from inside your eMac, the internal speakers have the capability to emit those same frequencies (117Hz or 85Hz).

    Before continuing, some defenitions for the explanation in the paragraphs that follow:
    Interference is the interaction of two waves.
    In phase is the interaction of two waves whose peaks and troughs occur at exactly the same moment. The wave that results from the two interfereing waves has an amplitude of the amplitude of the first wave plus the amplitude of the second wave. (Think of it as the graph: y = sinx + 3sinx)
    Out of phase is the interaction of two waves in which every peak of a wave interferes with the trough of another, and thus every trough of one wave interferes with the peak of the other. The resuling final wave has a smaller amplitude than the wave with the largest amplitude. (Think of it as the graph: y = sinx + 3sin(π/2-x))
    Beat is the frequency emitted by the combination of two waves of different frequencies. For instance, if your monitor emitts a frequency of 85Hz and the sound is 120Hz, then the beat is 35Hz.


    If the amplitude of the emitted sound waves of a frequency equal to the refresh rate of your monitor is high enough, then the sound waves will interfere with your monitor - especially if you are using any sort of a CRT monitor. The result of the interference of the two waves can be in phase or out of phase. If they are out of phase, or mostly out of phase, then both the amplitude of your monitor waves and the amplitude of the sound waves will decrease. If the waves are completely out of phase, some colors will not display properly because they were completely out of phase with the sound waves and thus lost some amplitude. The resulting color damage on the area of your monitor most affected by the interference of those sound waves is permanent!!

    The "wave" effect you see on your monitor is the result of your monitor and speakers emitting different frequencies. In the example for the defenition of beat, I subtracted one frequency from the other to get the correct solution: 35Hz. That's how many times a second your monitor "flickers." The waves are not in phase or out of phase, because the frequencies of each wave are different. The effect on your monitor is that flickering.
     
  6. phreakout13 thread starter macrumors 6502

    phreakout13

    Joined:
    Jan 4, 2004
    Location:
    South Eastern MA
    #6
    thanks:) I have some external speakers I can use, as well as a round elecromagnet thingy used for fixing televisions with that problem.
     

Share This Page