Help with box build..

Discussion in 'Audio & Electronics' started by TLSF150, Oct 7, 2011.

  1. TLSF150

    TLSF150 Full Access Member

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    Okay so I plan on build a new box this weekend.. Im going to end up goin with 1 of the PR12s in a larger ported box that will just sit in the back seat..

    Heres what I got so far..

    [​IMG]

    [​IMG]

    So im looking at around 2 cubes after the port volume is subtracted and tuned to 35Hz.. My goal was 36Hz but 35 seems close enough I wont notice a difference..

    What do you guys think?? Should I change anything?? I dont know alot about this kinda stuff im just going off stuff I read at stevemeadedesigns.com..

    This is going to be the first box ive built so any tips are appreciated..
     
  2. supercrewzn

    supercrewzn Full Access Member

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    Use screws and predrill holes!
     
  3. Roush PSD Interceptor

    Roush PSD Interceptor 7.3L Straight Piped Diesel

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    Looks like a SMD has a great volume calculator there.
    3/4 MDF is about $22 a 4x8 sheet here.

    Wait for caulk / sealant to cure before loading sub into the box.

    Use some kind of retaining straps that you can run the seat belts thru,
    that box can become a missile / wrecking ball during an accident, secure it.
     
  4. TFIDDLE

    TFIDDLE VEEEE TEn

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    What calculator is that

    Sent from my SCH-I500 using Tapatalk
     
  5. cowboy

    cowboy Sheriff

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    damn they have calculators now and its got all scientific.
     
  6. TLSF150

    TLSF150 Full Access Member

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    Thanks for tips guys.. The calculator is from SMD I think its like Torres calculator IRC Ill try to find the link for it and post it up.. It makes it easy for people like me.. You just punch numbers in it till you get what you want..

    So 2 cubes @ 35Hz should be a pretty good size for 1 memphis 12 right??
     
  7. Bee89

    Bee89 Super Moderator

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    i forward this to my best friend, he knows his shat when it comes to subs. This is what he relayed to me:

    "hes not accounting for sub displacement ne needs to subtract i think its .15-.16 cuft for that and that probably will effect tuning freq and imho he nneds more port area"

    he also looked into the subs that you mentioned and said:

    "hes going below recommended tuning for those subs, box volume after sub displacement(airspace sub pushes out) is gonna be perfect 1.85cubicfeet, but he might loose performance being tuned so low. he should tune to 44hz. if he wanted better sound out of it he should go 2.25 cubic feet and tune to 38hz and be done with it."


    hope this helps alex :)
     
  8. Roush PSD Interceptor

    Roush PSD Interceptor 7.3L Straight Piped Diesel

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    The spec sheet that comes with PR 12's is":

    Sealed c.f. 1.25
    Vented c.f. 2
    Tuned Hz. 40

    Now some are saying up to 6 c.f. ported tuned between 30-35Hz.
    Though not everyone's ear is tuned the same so what sounds really good to some may not sound good to others.
    Some people say a M class is for sealed box design and people can say different sizes of c.f. ported vs sealed.
    Build the box that suites your taste in music and the sound you like it to produce.

    Bee89's friend brings up a good point that people don't account for the displacement of the sub itself.

    I would go with the specs Memphis is calling for, after all they made the speaker.
     
    Last edited: Oct 7, 2011
  9. Bee89

    Bee89 Super Moderator

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    thats pretty much what my friend said too

    "tell him to go with memphis's optimal setting for the subs, he really wont hear the diff between 35hz to 38 hz"
     
  10. TLSF150

    TLSF150 Full Access Member

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    Hmmm 2.25 and 38Hz or 2 cubes @ 40Hz... I think Bees friend probably knows what hes talking about..... But since this is going in my back seat I want to keep it as small as possible so that I still fit 2 passengers in the back.. Going to have to do some reworking and see what I come up with..
     

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