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  1. #1

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    Default Dual 505 Freq Sweep

    This has been a fun little project. I think I need to work on the room acoustics. I have two PSW505's stacked and corner loaded. For this test I put the Onk on a volume of 45. I would have liked to run it hotter but the bass police was home. I have individual tones for 20-99Hz.

    It was interesting to see which parts of the walls vibrated at different frequencies. I found that a vent in my ceiling makes an awful metal on metal vibrating noise at exactly 84Hz, no less, no more, just exactly 84Hz. I found that my loudest point is 48-49Hz, at 102db. My weakest point was at 20Hz, at 76db. It was really cool to see the db meter move at 20Hz, even though you couldn't really hear much of anything.

    Obviously, I would like my peak to be at the 30Hz and lower area. Maybe its just not possible, or maybe it is with the right room acoustics. Any pointers?

    Regards,
    PolkThug
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  2. #2

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    Are those corrected?

    That graph is not bad at all. Sure there is a slight hump at about 50 Hz but nothing too bad. You can get lower extension and a peak below 30 Hz with an PEQ, but you risk bottoming out the drivers below the tuning frequency. Try correcting the values if you havent already and you will see that the graph will have better extension.
    Graham

  3. #3

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    I didn't make any corrections. I think I remember something about you have to add db's at lower freq's for the Rat Shack meter. Can't remember the formula.....

  4. #4

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    Yep you have to add dBs, Pjdami posted the the correction factors in this post. http://clubpolk.polkaudio.com/forum/...0&pagenumber=2

    Where did you get your test tones from?
    Graham

  5. #5

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    Thanks.

    Bass Mekanik 5.0

    Money well spent. I'm going to go through this process again and isolate all my "vibrating spots" in the room. I got some Tsunami Silencer to put behind the walls where necessary and on my vent that likes to scream at 84Hz. lol

  6. #6

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    :-)

  7. #7
    Old School
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    PT,
    Since you're "expermintin' "... try draggin the stack about half-way out of the corner... One direction and then the other...

    102 dB??? Not a very strict police(wo)man is she? ;)
    More later,
    Tour...
    Vox Copuli
    Better to remain silent and be thought a fool, than to open your mouth and remove all doubt. - Old English Proverb

    "It's easy to get lost in price vs performance vs ego vs illusion." - doro
    "There is a certain entertainment value in ripping the occaisonal (sic) buttmunch..." - TroyD
    "Death doesn't come with a Uhaul." - Dennis Gardner

    Rebuilding Maggie 2-ch & Amazing 2-ch... Building 2-ch "wall"... Figuring out the HT

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