box size: recommended or custom size.

Discussion in 'Subwoofer Box and Custom Fabrication' started by deepbass, Dec 24, 2011.

  1. deepbass

    deepbass Full Member

    ok, so going to build this box tonight, or at least start cutting,

    so kenwood recommend a box size range of .80 to 1.75 cuft, of that range they say the best size for this sub is 1.25cuft,

    now my max box size is 3.22cuft (1.61cuft per driver)which is 30"w x 15 d x 16 h.

    should i build to kenwoods spec or what size i have avalible?

    then my next qestion which would define the above is, what difference in sound, bass and any thing else considered would 2.5cuft or 3.2cuft make?

    i ask because if kenwood (or any speaker company's specs) state this is the ideal box size then i would have thought it would be best to do so to get the best from the driver

    if it is housed in a lager box, how does this effect its thiele small parameters. ie excursion, resonance and the way it performs?

    in simple terms i guess, which size will produce the best sq bass and performce?
  2. Ranger SVO

    Ranger SVO Full Member

    OK here are the recommendations from your owners manual

    Kenwood ported.jpg

    Kenwood sealed.jpg

    Middle is typically the best compromise. But with sealed boxes, the performance is very close to the same even at both extremes. So size for a sealed box is not that big a deal. So a 1.5 cu ft to 2.5 cu ft will be plenty good enough. In a sealed box, the smaller will have a slight relative gain. So 1.5 cu ft would be the way to go.
    Last edited: Dec 24, 2011
  3. deepbass

    deepbass Full Member

    So i would have 1.6cuft per driver. What does that mean for bass. That itll produce very deep bass but lack the ability to hit faster bass beats
  4. Ranger SVO

    Ranger SVO Full Member

    Wait, are we talking about a ported box or a sealed box. If you want accurate bass then sealed, if you want extended bass response and loud then ported. Be honest with yourself. What do you want? Do you want to impress your friends? then port it.

    Box size does not effect Thiele/ Small Parameters.

    So what do you want?
  5. deepbass

    deepbass Full Member

    Sealed. I want clean bass i can feel and hear.i want it to hit most if not.all the notes a dubstep or drum and bass track can give it. I have no need to impress friends just my self.
  6. Ranger SVO

    Ranger SVO Full Member

    Then go with a box around 2 cu ft box. And thats for both woofers, 1 cu ft each. I would have them share the same enclosure, no divider. Also, can we down fire the box? We can pick up a lot of sound if we can front load the woofer. If we down fire, we can increase the size of the box for that really deep sound and have that really tight sound at the same time.

    Check out the box in my wifes car here. The sound is really good and its suprisingly loud.
    Last edited: Dec 24, 2011
  7. deepbass

    deepbass Full Member

    what i need is some one with a sub box designer, any one have one here? tried downloading one but hasnt worked.

    well ok that sounds good to me, 2cuft. i would rather not down fire, but if this is works better then i could build it this way. each sub says 1.25 each. so maybe im best building a little larger to 2.5cuft as you say

    ok got it working, put all the drivers details in on bassbox pro 6,

    says 1.2 cuft per speaker. so isnt far off kenwoods specs.

    im really in a back and forth decision here lol
    Last edited: Dec 24, 2011
  8. Ranger SVO

    Ranger SVO Full Member

    Box designer???? I just use a calculator

    I am assuming that we are using 3/4-inch MDF so here we go.
    The Box should be 28-inches wide by 14-inches tall by 15-inches deep.

    That means we need
    (2) 28-inches by 14-1/4-inches (1) top and (1) bottom
    (1) 28-inches by 12-1/2-inches back
    (2) 13-1/2 by 12-1/2-inches (1) left and (1) right side

    After the these pieces are together then we cut out the baffle board

    (1) 28-inches by 14-inches Baffle Board

    Look at the post here. Look at post #4, (pretend there is no port) and notice the brace between the woofer, you should have one between the two woofers. It will be 12-1/2-inches by 4-inches. You can also add one (or two) to the back wall, same dimensions. Look at post #2, you can see the brace on the back wall.

    Again, the baffle board is not cut until the rest of the box is done.
  9. deepbass

    deepbass Full Member

    Thanks ranger. Read your post u link a good week back. Really good guide

    what im trying to find out is recommended box(1.25cuft) or 1.6cuft which the upper range of what is writen. (0. 8 to 1.5)

    i can build either.

    And need to know if to put them seprate or together in on air space
  10. Ranger SVO

    Ranger SVO Full Member

    There is NO divider board in my parts list, so they will share the same airspace

    Now just in case you wanna downfire, the dimensions will be different. The downfire configuration will front load the woofer so the internal volume can be smaller without a penalty.

    For a downfire box, the box would need to be 30-inches wide by 15-inches deep by 10-inches tall. This one I do different

    (2) 30-inches by 15-inches (1) Top and (1) Bottom (baffle)
    (2) 30-inches by 8-1/2-inches (2) long sides
    (2) 13-1/2-inches by 8-1/2-inches (2) short sides

    The stands are not added until the box is together. The stands need to be 2.25-inches (three strips of 3/4-inch MDF glued together) and there should be ONLY one open side.
    Last edited: Dec 24, 2011
  11. deepbass

    deepbass Full Member

    Thanks. Is it ok to swap depth with hieght?
    And from your messurements. Your saying 2.5 cuft or the recommend box size

    Also as i will be bracing i need to make the box slightly larger then your messurements. Juat need to work out the overall bracing volume.
  12. Ranger SVO

    Ranger SVO Full Member

    It is OK to swap depth and height. My parts list cut outs will no longer be right.

    Do not adjust the box dimensions, the braces do not take up enought room to justify changes
  13. deepbass

    deepbass Full Member

    Ok thanks. Massive help! Well if theres a section. Ill get pictures making and when done.
  14. Baez8669

    Baez8669 Full Member

    Need help on enclosure can u help