Polk LS50 buzz

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Hello all. One of my LS 50 speakers has developed a buzzing in the middle speaker (midrange? looks just like the bottom one?). I inspected it and found no damage to the cone or suspension. I also removed it from the case and found nothing in contact with the cone etc. and the wire connections looked tight and good. Checked my wires from the receiver and connections there and the problem stays with the one speaker so I think everything like that is ok. So, I need advice. What do I check from here and how do I repair it? Thanks

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  • F1nut
    F1nut Posts: 49,794
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    Tighten the mounting screws.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • ddog
    ddog Posts: 230
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    Luckily all the parts you might need are on fleebay
  • kymike
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    To clarify, this is not a mechanical interference buzz. Rather the sounds produced by this speaker have a garbled, fuzzy, distorted sound which is sometimes more obvious than others. What I'd like to know is what components or faults are likely to cause this (loose wire connection, bad crossover, etc.?) and how to diagnose without a random parts swap out.
  • pitdogg2
    pitdogg2 Posts: 24,559
    edited December 2018
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    Polk LS50? Switch the speaker with the problem to the other side. If your problem follows then it is fact the speaker itself. Before you unscrew the speaker put a piece of small tape at 12 o clock on the speaker to know that you are in fact keeping the speaker orientated in the same position it was in the original speaker. This may sound strange but some of the older Polk drivers get a buzz after the surrounds get a little weak. Kind of like a speaker sag. So if the buzz follows the speaker into the new speaker you do know in fact it is the driver. So now that you have the tape and the driver in the same position take that driver and turn it 180°degrees so the tape is now at the 6:00 position. I know this sounds weird but sometimes it works and the driver works okay afterwards I've had two drivers that I've had to do this with. Just a thought but it doesn't hurt to try. Now that you found out it is the speaker itself you can get the number off the back of the speaker and start doing a search on the selling sites and try and buy another driver or you can call Polk and see if they have any that I doubt.
  • ddog
    ddog Posts: 230
    edited December 2018
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    I'd try to locate where the unwanted sound is coming from. You can use a piece of PVC pipe a foot or two long up to your ear on one end and the other pointed at or around each driver. If it's a driver or the tweeter then I'd disconnect it to make sure that eliminates the problem. If that doesn't work then it most likely will be the cabinet.