Who can explain Phase to me?

Discussion in 'Beginners, General Questions' started by Anthony_I, Oct 24, 2003.

  1. Anthony_I

    Anthony_I Stunt Coordinator

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    I still have no real idea what phase is, how it changes hte sound or why. and anything ive found on the net has either been not clear enough or simply far far too technical for me to understand.

    So what is phase and how does it work/what does it do?
     
  2. GrahamT

    GrahamT Supporting Actor

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    Phase is like the polarity, hope this helps

    If the speakers are out of phase (polarity), one will move in, while the other moves out. The displaced air from one is sorta cancelled out by the other moving in at low frequencies. It is kind of like one speaker in free air. It will produce almost no bass.
     
  3. Anthony_I

    Anthony_I Stunt Coordinator

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    so what does adjusting the phase on my amp do?

    I mean i understand it as far as moving in/out goes.... but thats about it, and your explination actually told me a little more than i already knew. [​IMG]

    But im talking about my subwoofer, a single speaker with a continusly adjustable phase.
     
  4. Wayne A. Pflughaupt

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  5. GrahamT

    GrahamT Supporting Actor

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    I understand. I just meant that if he reversed the polarity of one of the two speakers that they would be out of phase with each other. I thought that this was his question. Sorry if I wasn't clear.
     
  6. Anthony_I

    Anthony_I Stunt Coordinator

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    That makes a little more sense.

    I guess i would hear a difference more if i had speakers other than a sub and some VERY VERY VERY VERY horrible mains (im actually using 2 "surround" speakers from a mini stereo system. simply to get some treble, until i got money to get my mains)
     
  7. Ted Lee

    Ted Lee Lead Actor

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  8. John Garcia

    John Garcia Executive Producer

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    I auditioned the Q1s with some very nice gear, and I was not impressed. My friend has some Q5s and they sounded pretty good, in a less than optimum room, so I was surprised that the Q1s did not hold up. The Q1s had depth and imaging, but no "life" to them.

    The crossover can also be used to "align" the phase of the drivers.
     
  9. Ted Lee

    Ted Lee Lead Actor

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    oh...i actually agree with you john. i had some older uni-q's that were floor-standing (can't remember model number). they sounded much better than the bookshelf model.

    i was just using that link as an addendum to explain wayne's post.
     
  10. Allan Jayne

    Allan Jayne Cinematographer

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    Speaker phasing is most important for bass, and in this context polarity and phase go hand in hand. So long as all the speakers are connected the same way, for example red or plus terminal on the amp to red or plus terminal on the speaker, the system should be properly phased.

    For middle range and treble, the phase of the sound waves as they reach your ears can vary depending on where you are sitting in the room. Because this is a very complex acoustical topic, I do not think that setting back the tweeter in the speaker cabinet to make it sonically in phase with the woofer has any importance.

    Speakers in general do not have flat frequency response. Also, resonances in the room will alter the frequency response as you hear it. Even your ear may be more sensitive to certain frequencies than others. Therefore to you certain speakers may sound much better than others and other folks may disagree. I believe that these differences are much greater than any time matching or phasing of the mid range or tweeter speakers could possibly accomplish.

    If you have a different brand amp for your rear speakers versus your front speakers, it is possible that the audio arriving at the speaker terminals of one amp is partially out of phase so that connecting the speakers all with the same polarity does not work well for bass.

    Video hints:
    http://members.aol.com/ajaynejr/video.htm
     
  11. John Garcia

    John Garcia Executive Producer

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  12. Ted Lee

    Ted Lee Lead Actor

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    b&w are another good example of time alignment considerations. take a look at this link.
     

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