Need "expert" 1803/PR opinions

Discussion in 'Archived Threads 2001-2004' started by JimPeitersen, Oct 2, 2002.

  1. JimPeitersen

    JimPeitersen Second Unit

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    Guys,
    I have been playing with Winsid Pro, and have a few questions about PR's for an BP 1803 box. Perhaps I am misreading the graph, but I don't see were the Styke 18" PR's run into trouble in any reasonable box size (even when I model using only one of them.) Am I missing something? I would like to get some of the 18's that are on preorder, but I am not sure which model and alignment would work the best. Power is not a problem, and I have a BFD. Thanks in advance.
    JP
     
  2. Chris Carswell

    Chris Carswell Supporting Actor

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    I'm not sure.....
    The 18" Pr's have a xmax of 25mm (50mm p-p) with a Sd of 1200 cm^2 = vd of 6L. From what I gather the BP 1803 has a xmax of 25.9mm (51.8mm p-p) and a Sd of 1217 which if my math is correct = vd of 6.3L . With one I think you are cutting it a little close. I'd go with two JTBS [​IMG] .
     
  3. JimPeitersen

    JimPeitersen Second Unit

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    Chris,
    That is what I thought also, but John J. corrected the figures for the 18" models on another thread (and his site.) They have a 3" (75 mm p-p) xmax and can displace about 9 liters. I understand the need for excess excursion, but at what point does adding a second PR become unnecessary?
    JP
     
  4. Dustin B

    Dustin B Producer

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    Jack G will hopefully jump in soon. But the rule of thumb with PR enclosures is to have at least twice as much Vp as you do Vd. If the 18" PRs are actually 9L of Vp then a pair should be fine with a 6.3L Vd driver, but one would not be ideal.
     
  5. Jack Gilvey

    Jack Gilvey Producer

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    I don't post when "experts" are called for, but since my name was mentioned...


     
  6. JimPeitersen

    JimPeitersen Second Unit

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    I think it has been mentioned before, but it looks like a simple vented box would be the best choice for this driver. An LT would work also, given the excursion and power handling of the driver. Thanks for the opinions though.
    Jack, what PR box do you like for this driver?
    JP
     
  7. I agree. If PRs are the route, then dual opposed is the ONLY way to go. This driver ported will use a large enough enclosure such that an 8" port will not be too long.
    Take a look at Brian Ownens ported enclosure with the 1803.
    http://bkolfo4.freeservers.com/photo.html
    I would use the 1803 in a 360L enclosure @ 18hz.
     
  8. Hey Mr. Expert, who asked you what volume was appropriate [​IMG]
     
  9. Dustin B

    Dustin B Producer

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    Ha, neither of you know what you are talking about :p) I'm the only real psuedo expert here [​IMG] I say it should be 380L tuned to 18.5hz with an 8" port [​IMG]
     
  10. JimPeitersen

    JimPeitersen Second Unit

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    You guys are letting this "expert" thing go to your heads. [​IMG] It is actually a fun driver to play around with though.
    JP
     

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