Resonating bass on SDA SRS?

FheBlackPassat
FheBlackPassat Posts: 42
edited November 2010 in Vintage Speakers
I can hear some wierd noise on mine at very specific frequencies. I swear its the PR basket resonating on certain notes that are struck with a bass guitar.

Has anybody else experienced such an event on their SDA SRS's?
Post edited by FheBlackPassat on
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  • ben62670
    ben62670 Posts: 15,969
    edited November 2010
    Pull the passive out and see if the spider is damaged.
    Ben
    Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
    Thanks
    Ben
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  • AudioGenics
    AudioGenics Posts: 2,567
    edited November 2010
    check placement of the speakers
    also make sure that nothing external is vibrating.
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  • ben62670
    ben62670 Posts: 15,969
    edited November 2010
    Also check and see if all the driver screws are tight.
    Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
    Thanks
    Ben
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  • F1nut
    F1nut Posts: 50,567
    edited November 2010
    The paper/Styrofoam parts at the rear of the PR have been known to come unglued resulting in odd sounds. Remove the PR and if that is the problem, it will be obvious.
    Political Correctness'.........defined

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  • Audioquest
    Audioquest Posts: 104
    edited November 2010
    FheBlackPassat wrote: »
    I can hear some wierd noise on mine at very specific frequencies. I swear its the PR basket resonating on certain notes that are struck with a bass guitar.

    Has anybody else experienced such an event on their SDA SRS's?

    Pull the drivers and see if any of the wiring is vibrating against the inside of the enclosure. I know most speaker manufacturers never do much to secure the wiring so this won't happen.
    HT: Polk SDA SRS 2.3 main fronts, Klipsch RC-25 center channel, Polk RTi-150 rears, M&K V1B sub, Denon AVR-5800, Samsung 52" LCD, Sony BDP-S550

    2 Channel: Carver ALS Platinum, Audio Research LS-2B preamp, Counterpoint SA-100 amplifier, Integra CD player, Denon SL7D tt, TC750 phono pre, Nikko tuner
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  • FheBlackPassat
    FheBlackPassat Posts: 42
    edited November 2010
    Well I've done all the obvious external checks. Next step, take out the PR and start investigating. What it sounds like to me is that at certain frequencies the basket on the PR is resonating. I can't say 100% for sure but it sure sounds metalic to me.
    If this helps at all, I really notice it when I listen to the Tool
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  • AudioGenics
    AudioGenics Posts: 2,567
    edited November 2010
    some folks apply a "dynamat" sound absorbing type material on the basket

    http://www.dynamat.com/products_architectural_dynamat_xtreme.html
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  • FheBlackPassat
    FheBlackPassat Posts: 42
    edited November 2010
    Oh really?! So I'm not just hearing things? Dynamat, know it all too well. Many an hour applying it to the inside of my car.
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  • dorokusai
    dorokusai Posts: 25,577
    edited November 2010
    F1Nut and Ben have already pointed you in the right direction.
    CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
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  • AudioGenics
    AudioGenics Posts: 2,567
    edited November 2010
    yeah definitely need to verify all the component ie passive radiators are in good condition

    also do a search on dynamat
    there are lots of threads

    here is one interesting one for example
    titled : Fun With Foam: SDA Driver Basket Insulation

    http://www.polkaudio.com/forums/search.php?searchid=16612440

    http://www.polkaudio.com/forums/showthread.php?t=74306&highlight=dynamat+darqueknight
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  • OldmanSRS
    OldmanSRS Posts: 419
    edited November 2010
    Check the front to back braces inside the cabinet. They are hot glued and known to break loose.
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  • FheBlackPassat
    FheBlackPassat Posts: 42
    edited November 2010
    Holy crap, I'd like to listen to my speakers for a while before I rip them all apart:smile:
    Oh well, might as well get this stuff over with. This is a good weekend project without kids around. Ill have to figure that one out. Yeah right.
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