Port MM2104s?

Systems
Systems Posts: 14,873
edited April 2005 in Car Subwoofer Talk
Hey its me again, just wondering if porting 2 x MM2104s would be a good idea? I've heard that a polk subs don't do well in a ported enclosure. I figured I would try both and see which I liked better, but I dont want to cause any damage to my subs in doing so. My enclosure is rated at 1.0 cubic feet [It's a q-logic] . Also do you think my setup will be a good one--

2 x MM2104
1 x 500.1 mono amp
4 x 6.5" infinity kappa speakers [no amp yet but I may get one]

Thanks a lot, sorry if this sounds dumb but I'm still new at this.

P.S. not really looking for a super good setup, just one that can deafen me a little bit more ;)
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Post edited by Unknown User on

Comments

  • neomagus00
    neomagus00 Posts: 3,899
    edited April 2005
    i like the setup, and i think you'll end up deciding to amp the fronts.

    there's no reason not to try a ported box, especially if you have one sitting right there. since it has 1.0 ft^3 per chamber, and the mm2104 takes up roughly .05 ft^3, you need to tune for 26.9 liters. if you want to play around with it, unibox is a great tool (the macros are safe, and it doesn't work in openoffice). how big is the port in that enclosure (diameter)? and how long is it to begin with?
    It's not good, very fundamentally simply not good. - geolemon

    "Its not good enough until we have real-time fearmongering. I want my fear mongered as it happens." - Shizelbs
  • MacLeod
    MacLeod Posts: 14,358
    edited April 2005
    Using a ported box for the Momos wont hurt them. Its just that they were designed for max SQ in a sealed box but as long as the ported box is built to spec, they will work fine.

    Your setup looks good. Ill second the nod for getting an amp for the fronts too.
    polkaudio sound quality competitor since 2005
    MECA SQ Rookie of the Year 06 ~ MECA State Champ 06,07,08,11 ~ MECA World Finals 2nd place 06,07,08,09
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    polkaudio SR6500 --- polkaudio MM1040 x2 -- Pioneer P99 -- Rockford Fosgate P1000X5D
  • Systems
    Systems Posts: 14,873
    edited April 2005
    Hey the box is --

    Height
    14.8 inches

    Width
    32.0 inches

    Depth
    8.3 inches

    [It's the QLH-1.0010DE and holds 2 x 10"]

    I have a 2000 Toyota Corolla in really nice condition, do you think I would need to get a bew battery or alternator if I decided to amp my speakers? The speakers are 50 watts rms, so do you think a 400x4 amp would be good or would that be overdoing it? Thanks for helping me out
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  • Systems
    Systems Posts: 14,873
    edited April 2005
    oops, forgot the port dimensions

    Port-

    3" wide by 12" long

    Thanks again
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  • neomagus00
    neomagus00 Posts: 3,899
    edited April 2005
    w00t! i love box design! no, really, i actually do.

    actually, you should just leave the port as long as you can. this'll tune that box to almost exactly 35 Hz, which is perfect for the 2104. if you leave polyfill out, you can get about a 2dB bump at about 57 Hz, right in the 'kidney-punch' range. you may like this, but if you don't, the more polyfill you add, the smaller that bump gets. you'll reach a point where more polyfill begins to push the low-frequency response down, and that's bad. i'd say cover the walls with it and be done.

    'according to my calculations', you'll get about 113 dB out of it freeair, probably more, especially in the lower registers, in-car.

    note that you can cut the port shorter to provide a bigger bump at some higher frequency, but you'll lose low-range extension. the full 12" is most likely your best bet, and keep in mind you can't lengthen the port once you've cut it...

    oh, yeah... you may want to upgrade to an optima battery, but you don't need an alt. a true 400x4 amp is crazy. i think you meant 400.4, which divides 400 watts into 4 channels, but doesn't tell you at what impedance. for example, polk's C400.4 does 100x4@2 ohms, but 75x4@4 ohms. that would be a slight overpowering. you want an amp that's rated at 50x4@4 ohms, and there's a lot of em. depends on budget.
    It's not good, very fundamentally simply not good. - geolemon

    "Its not good enough until we have real-time fearmongering. I want my fear mongered as it happens." - Shizelbs
  • Systems
    Systems Posts: 14,873
    edited April 2005
    Yeah, 400.4 is what I meant lol, Thanks a lot for the info and advice, it means a lot to a n00b like me :) If I'm not mistaken 100db or over is good right? I'm just curious because I have a friend that makes really heavy techno [his songs have more bass than GOD lol] and I just wanna show off a little ya know?
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  • neomagus00
    neomagus00 Posts: 3,899
    edited April 2005
    113 dB is pretty respectable, yes. you won't win competitions, but it'll be plenty loud. a note of caution: playing it at that volume can and will damage your hearing permanently. fyi.
    It's not good, very fundamentally simply not good. - geolemon

    "Its not good enough until we have real-time fearmongering. I want my fear mongered as it happens." - Shizelbs
  • Systems
    Systems Posts: 14,873
    edited April 2005
    :) just what I wanted to hear

    Thanks again.
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