Closed Thread
Results 1 to 8 of 8

Reload Thread: Polyfill for SPL

  1. #1
    shizzzon's Avatar
    shizzzon is online now I am who you think I am



    Join Date
    Apr 2008
    Location
    KY
    Posts
    569
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Polyfill for SPL

    I've reached a point where cutting off the port length is losing SPL...

    The best port length i have is 18" though due to port area size, bla bla bla...

    if i keep shortening the port length, port tuning will go up and i start to lose dbs at my peak frequency...

    So... if i were to start adding polyfill in the box... would this actually start to lower my tuning AND help me to keep gaining SPL? or does polyfill prohibit increases to pressure?







  2. #2
    Louisiana_CRX's Avatar
    Louisiana_CRX is offline dem shoes......



    Join Date
    Aug 2006
    Location
    Piney Hills of Louisiana
    Posts
    34,137
    Post Thanks / Like
    Images
    9
    Mentioned
    31 Post(s)

    Re: Polyfill for SPL

    i've seen polyfill where it got so hot it actually melted to the magnet of the sub...lol




    Current 2010 Louisiana USACi State Records :

    Trunk 0-1000.................. 151.3
    StreetBeat 2................... 145.6
    Stock 1801-up.................153.8
    SuperStock 1801-up..........154.2
    Top three in 11 out of 26 power classes and Louisiana USACi Points Leader at 465

  3. #3
    Pioneer~Saturn's Avatar
    Pioneer~Saturn is offline Dr. Enclosure



    Join Date
    Jul 2006
    Location
    Dayton, OH
    Age
    25
    Posts
    5,318
    Post Thanks / Like
    Images
    7
    Mentioned
    1 Post(s)

    Re: Polyfill for SPL

    I wouldnt think polyfill would help get louder



    <First and only dual-alternator 'real' Saturn (pre 2002) on the planet>
    Team Concepts, Team Shok Industries Team XS Power
    Soon: Mystery subs + AQ20k
    12.75 cubes net ~25Hz tuning 200 sq inches of port (lowz?)
    AC position- 250 amp alt
    Stock alt position- 225 amp alt
    (2) XS Power D3100's
    4 power+ 4 ground runs of 1/0-gauge to rear
    152.1 @ 40Hz legal, certified...just getting started.

  4. #4
    ciaonzo's Avatar
    ciaonzo is offline TheContinental



    Join Date
    Feb 2009
    Location
    WI
    Age
    39
    Posts
    9,182
    Post Thanks / Like
    Mentioned
    32 Post(s)

    Re: Polyfill for SPL

    Polyfill gives the driver the impression it's in a larger enclosure than it's actually in.



    Quote Originally Posted by audioholic View Post
    Saying "clipping doesn't kill speakers" is a half-truth at best. Technically no, clipping itself does not hurt the speaker. But in clipping your amp, you can easily create a situation that WILL kill the speaker. Was the squared waveform the DIRECT cause of the failure? No. In the end, the answer is, always has been, and can only be... heat kills speakers. BUT, clipping increases heat generation, sometimes by a drastic amount. So to start a thread simply to state that clipping does not hurt speakers is, again, a half-truth at best.

  5. #5
    shizzzon's Avatar
    shizzzon is online now I am who you think I am

    Threadstarter


    Join Date
    Apr 2008
    Location
    KY
    Posts
    569
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Polyfill for SPL

    well, that's why i dont know what will happen.

    Either it will lower my tuning which i know it will if used but while lowering tuning to a point where shorter ports will peak closer to my car's peak... will this continue to start increasing spl again as tuning get's closer to car's peak or will the polyfill actually somehow, i dont know how to explain it, just plain prevent an increase in pressure like trying to use a small port area instead of a large one...




  6. #6
    shizzzon's Avatar
    shizzzon is online now I am who you think I am

    Threadstarter


    Join Date
    Apr 2008
    Location
    KY
    Posts
    569
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Polyfill for SPL

    maybe i didnt explain enough...

    I had a 25.5" port length and i start cutting little by little off until i got the loudest...

    My loudest is using an 18" long port...

    The only way i can continue to gain spl is by increasing internal volume...

    I know polyfill gives this effect. So, by using the same port area, if internal volume increases, tuning decreases as well.

    So it's like a win-win situation in my case. I need to keep testing ports but i cant until i take another approach and this is the next one...




  7. #7
    killa101's Avatar
    killa101 is offline Senior VIP Member



    Join Date
    May 2009
    Location
    Michigan
    Posts
    214
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Polyfill for SPL

    You could cut the port down more after you add the polyfill if you feel it gives you more output.

    Polyfill will absorb some energy so you may lose a little SPL. I don't know all the info but the increase in SPL from a larger internal volume may not be very large due to the loss from adding polyfill.



    Refs:
    eBay user name: davici67zc
    Sold to: MCarmer, lopaka, chuck5766 (caco), sacking74, Jelani_ellis (caco), tankglh21 (caco), bobbarker (caco)
    Bought from: whitedragon551, fasfocus00

  8. #8
    Immacomputer's Avatar
    Immacomputer is offline Cloud disappear



    Join Date
    Sep 2006
    Location
    Ocala/Oviedo, FL
    Age
    29
    Posts
    4,641
    Post Thanks / Like
    Mentioned
    0 Post(s)

    Re: Polyfill for SPL

    Quote Originally Posted by shizzzon View Post
    The only way i can continue to gain spl is by increasing internal volume...

    I know polyfill gives this effect. So, by using the same port area, if internal volume increases, tuning decreases as well.
    That's not really how polyfil works. It dampens the response, not make the enclosure volume seem larger. Making an enclosure larger can help dampen a response as well but they don't really share any other properties. Polyfil is rarely going to gain you any output as it is meant to dampen peaks and smooth in valleys.

    Try it and see though.



    Video 1
    I may make you feel but I can't make you think.
    Your sperm's in the gutter -- your love's in the sink.
    Video 2

Closed Thread

Posting Permissions

  • You may not post new threads
  • You may post replies
  • You may post attachments
  • You may edit your posts

1e2 Forum