Would this Woofer work for a Home Sub?

Discussion in 'Archived Threads 2001-2004' started by Bill Street, Aug 28, 2002.

  1. Bill Street

    Bill Street Stunt Coordinator

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    Partsexpress has what appears to be an excellent deal on this VIFA Woofer
    http://www.partsexpress.com/pe/pshow...number=299-229
    It states it is designed for auto sound, but would it be acceptible for Home use?
    Forgive me if the answer is obvious, but I'm new to DIY projects. What I'm looking for is a replacement driver for my RCA/Optimus SW Pro 100 sub. I got some great suggestions for improving sound and I've filled it with pollyfill and sealed the port. But the driver is still substandard.
    Thanks for any help.
    Bill S.
     
  2. Brian Bunge

    Brian Bunge Producer

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    Bill,
    I think the Qtc=.77 is way too high for home use. IMHO, you'd be much better off with one of the Dayton 10" drivers.
    Give us the internal dimensions of the enclosure and we can see if it will work well in it or not.
    Brian
     
  3. Bill Street

    Bill Street Stunt Coordinator

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    Thanks Jack & Brian,

    This forum is a great place to get information! The dimensions are 14"x 14"x14". It appears to be 3/4 MDF but I'm not absolutely certain.

    I plugged the external dimensions into a cubic foot calculator and came up with 1.59 cubic feet. I put about 28 -30 ounces of polyfill in there. I'm at work so I'm not certain about the diameter or length of the port, which I was advised to seal.

    I was told the 10" Titanic would be a top choice, but honestly I can't afford it. Is there a less expensive alternative to give some good results?

    Bill S.
     
  4. Brian Bunge

    Brian Bunge Producer

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    If the internal dimensions are 14" cubed, then yes that's 1.59ft^3. I'll see if the Dayton I mentioned will work well in that enclosure later tonight.
    Brian
     
  5. Mark_E_Smith

    Mark_E_Smith Second Unit

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  6. Bill Street

    Bill Street Stunt Coordinator

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    Hi!

    Thanks Mark. If I were to use one of those drivers should I keep my port sealed? Also, I take it that I would not need most of the polyfill I've added?

    I'm still interested if the recommendation from Brian would work for my system.

    I have some knowledge on this issue, but is there a good thread for DIY Sub beginners?

    Thanks

    Bill S.
     
  7. Brian Bunge

    Brian Bunge Producer

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    Bill,

    Sorry, I didn't have time to look at it last night. OK, the driver I mentioned would have an F3 of 51Hz in a sealed enclosure with heavy fill.

    Now if I use the same sized ported enclosure for this driver tuned to 30Hz you'll have an F3 around 33Hz and an F6 around 28Hz. So you'll have decent output to the mid/high 20's. If you use a 3" diameter port it would need to be right at 10.5-10.625".

    Brian
     
  8. Mark_E_Smith

    Mark_E_Smith Second Unit

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    You would keep it sealed, the HiVi F10 models a little flater and may be worth the extra cost. It also has more cone travel so it can go lower at higher spl. You would need to damp the walls only as the Q is .48 to .5 or you could add something to the volume to take up some space. then listen to it and see how it sounds. I could run the numbers for a ported if you like.
     
  9. Bill Street

    Bill Street Stunt Coordinator

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    Thanks once again guys!

    Mark if you would run the numbers for a ported enclosure I would appreciate it. Brian thanks for taking the time to run numbers with the woofer you suggested. I would like to compare and then decide which driver I should purchase.

    I appreciate all your help

    Bill S.
     
  10. Mark_E_Smith

    Mark_E_Smith Second Unit

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    OK this is real important for a ported box. Are the dimensions of 14" cube INTERNAL or EXTERNAL?

    Assuming a 6 dB room rise beginning at 50 Hz.

    If they are internal then you would have a Vb of 1.59 cu in and you would need a port of 2.5" x 8" tunning at 29 Hz and F3 of 40.5 Hz.

    If they are external I would leave it sealed as it is only marginally higher spl from 35 Hz to 40 Hz and worse below 35 Hz. You would need a port 2" x 5.5" tuning at 33 Hz and F3 of 47.5 Hz

    Sealed sub, Qtc .448 and F3 of 75 Hz
     
  11. Bill Street

    Bill Street Stunt Coordinator

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    Hi!

    Hope everyone had a great Labor Day Weekend! The 14" cube are external dimensions. I realize that for accurate specs for sub drivers we need internal dimensions.

    It appears to be 3/4 MDF that the enclosure is built out of. This should leave interal dimensions as 12.5" cubed. I know that is an assumption and I know what what assuming does...

    How badly does this throw off the specs for the drivers being considered? I have downloaded the recommended programs but cannot seem to get them to work correctly, which is probably my lack of knowledge showing up.

    Thanks again for everybodys' help!

    Bill S.
     
  12. Brian Bunge

    Brian Bunge Producer

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    Well, this makes things a bit tougher. Using only 32L (your 12.5" cube) gives an F3 around 38Hz and an F6 around 32Hz. Not a huge difference but it will affect output below 30Hz more. Also, you wouldn't be able to use a 3" port as it would be too long. A 2" port would need to be 6.5" long.

    Brian
     

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