Ported vs. Sealed Enclosure

Discussion in 'OT Technology' started by Bcr821, Jul 14, 2005.

  1. Bcr821

    Bcr821 New Member

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  2. XR250rdr

    XR250rdr OT Supporter

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  3. P07r0457

    P07r0457 New Member

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    I'd recommend a better sub. $200 gets a decent Elemental Designs e10o.v2, or something along those lines.

    But you haven't listed your requirements... Sealed boxes are smaller... They are tighter, have better response, imo. Ported boxes can be louder. Sealed boxes will go lower... Ported enclosures must have a SubSonic Filter to prevent the sub from playing under the tuning frequency... otherwise damage may occur to the sub. Sealed are also much easier to make.
     
  4. ledzep73

    ledzep73 New Member

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    A ported box is 3 db louder. You can either double the power, add another sub, or port a box to get a 3 db gain. If you port it, you do loose a little bit of SQ, but most people won't notice it. If you wnat a louder system, go with ported.
     
  5. Bcr821

    Bcr821 New Member

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    The sub was right at 50% off and i got it for $94. Not a bad deal. I have a sealed enclosure at the moment and was just wondering if it would be worht it to construct a ported

    I'm running this amp if it matters:
    MRP-M350

    Also got that at about 50% off...it cost me $114
     
    Last edited: Jul 14, 2005
  6. veonake

    veonake OnT poster, OT lurker

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    I'm pretty sure ported enclosures generally will extend lower than sealed boxes. As you know, sealed boxes create a natural slope attenuation that is steeper than a ported box.

    To the thread starter (to add): Ported boxes are also more difficult to tune. A sealed box is much more forgiving. You also have to watch out for port breathing noise. That can get annoying. I'm beginning to wonder if sealed boxes really have any better SQ, as on one of the forums I frequent (diy-audio), which consists of audiophiles that have been doing audio for a long time (most are in their 30's-40's I'd say), most people seem to be building ported enclosures.
     
  7. DaddyThirdLeg

    DaddyThirdLeg SMASH puny humans

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    If you tune a ported box low, say around 25hz-35hz, it will go low enough for most music, (unless you are listening to pipe organs) and sound just as good as sealed.

    The reason most people think ported isn't for sq is because most prefab boxes are tuned to 40hz-45hz this gives them a a big peak but they can't hit the lower bass notes
     
  8. XR250rdr

    XR250rdr OT Supporter

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    You have it reversed. Sealed boxes roll off at 12dB/octave and ported boxes roll off at 24dB/octave. Ported boxes dont suffer from cancellation as early though so they can extend lower in room. In a car the 12dB/octave cabin gain paired with the right driver/box can yield output down to nearly continuity.

    DaddyThirdLeg made a good point. Prefab ported boxes really have made all ported boxes look bad. One of the problems ported boxes can have, besides a peaky response curve, is higher group delay (basically the driver/box system slew rate). Group delay changes with regard to frequency too. Now higher group delay isnt bad if the curve is almost flat, but a high tuned box almost always yields a peaky group delay plot as well as a peaky response plot. Radical changes in group delay will make for a nasty sounding subwoofer. Small changes in box volume and/or tuning can often make for wide changes in driver behavior.

    Thats why ported boxes are so much more difficult to build correctly. You have to balance box volume and port tuning (and to a lesser extent port area) to get nice looking response and group delay plots (not to mention power handling). With a sealed box you just have to pick a box volume that produces a response curve that suits your listening tastes but also supports the power level you are running. Group delay isnt usually an issue with a sealed box.
     
  9. JRock10

    JRock10 Active Member

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    in layman's terms, i think ported are a lot boomier. but they can be tuned lower, which gives the effect of lower frequency bass volume. i use ported in both of my vehicles, and listen to all sorts of music, and they sound good to me, which is what matters
     

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