ported/vented box for 2 kenwood kfc w3011

Hi Brad.  First, you can never get optimal performance from a premade enclosure for any speaker unless you get really lucky.  That being said, go ahead and give your speakers a try in the enclosure you describe as I don't think it will harm them, nor do I think it will perform all that well..  It may or may not be any "louder" than the system you currently have, but if you must, try it.

The terms ported, vented, etc. are all just another way of describing a bass reflex enclosure.  They all do the same thing.

No, don't just add a port to your existing enclosures, it will most likely not work well at all unless you really know what you are doing.  And yes, the port must face open air, preferably the same air space the woofers face towards.

Thanks for your opinion.  I don't think I want to order it just to "hopefully" get better results because that would be a waste of $90. (:  How much money could I expect to have to shell out if I attempted to build a custom enclosure to the kenwood's specs for a dual 12" ported enclosure with each chamber containing 2.0 cubic foot air space?

Also, aside from the fact that it would be a premade box, would it be the length of the vent that would cause the above enclosure with my subs in it to not sound very good or what?  The sealed boxes that I have came from the same place as the vented box that I am thinking about getting and they make very good boxes.  However, the boxes that I have now are just sealed, not ported.  I guess it would be a lot harder to make a good ported box. (:

thank you very much.

Brad

You must use sealed enclosure for this sub.  EBP of 29.6, where anything under 50 should be sealed.  Find EBP by dividing Fs of 45 by Qes of 1.519    Re:  https://inform3.kenwoodusa.com/manuals/kfc-w3011.pdf

This sub and the rest of your gear may just not be suitable for your desired sound.  This sub is not built for low bass extension but you could likely apply a more powerful amp to make it louder.  Look at the response graphs shown by the manufacturer...peakiness between 60 and 70 Hz in either type of enclosure.

Bottom line:  save your $90 on that prefab box and take some time to sort out your priorities.

My gear consists of a Pyle Dryver 2000 amp (200 rms x 4 channels) I have 2 channels bridged on each sub giving them 400 rms each (this is their rated rms power,) of course the two subs above, 4 gauge amp wires, 1.2 farad capacitor, with a Sony CDX-R505 head unit.  Also, 6 other after market speakers in the factory locations of a Dodge Intrepid (1997.) 

I have looked at the WINlsd program this forum talks about so much, and if I have done it right I can build a 4 ft ^3 ported box with 2 x 4" diameter and 10.75" length ports to tune it to 35 hz and hit a flat 30 hz note with these subs.  I am not sure what a 30 hz note sounds like, but with what I have been reading the last 2.5 - 3 months is it is prreettyy low, which would be what I am looking for, i hope.  Is the WINlsd program accurate in what it says to build?  If I build this box that it recommends, will the box actually work to produce the sound it says it will?  How many of you have built a box with the WINlsd program and had it work like it says it will work?

Also, can any of you give me an average figure on what a box like this would cost to build?

Thanks to all that reply.

Brad

depending on how much the material cost in your area is what the final cost will be.  for me, i can build an enclosure myself for 60-80 dollars. this includes carpet, wood screws, mdf, glue,silicone,weather striping,terminal cups, and wire. 

bw40584, like Steve said those woofers will never really give you much extremely low output and they are best suited to a sealed alignment.  If you really want bone-rattling low end, you will have to get different woofers.  Oh, and get a real amp too while you're at it as Pyle is, well, appropriately named. 

WinISD is one of the best speaker enclosure design packages available and yes, for the most part you can "believe" what it tells you.  Realize that the actual installation will have a great deal of impact on the actual performance in a vehicle and you may or may not realize what any program shows you.  Another piece of excellent free software for designing subwoofers is called Unibox.

Hello.  I have decided that I need to build my own ported box for my KFC-W3011 Kenwood subs 2 12".  I was going to go with a prefab, but after discussing it on this forum and playing around with the WINISD program I decided to give it a go.  Here is what I plan to build:

Dual "common chamber" 12" ported box

Width:  37.5"     Height:  15.5"   Depth:   17.5"

Outside dem. volume:   5.88650  ft^3            Inside dem. volume:    4.66667 ft^3

Round ports:    Diameter:   4"    Length:   10.5"    Displacement=    .07636 ft ^3  x  2  =  .15272 ft^3

Driver displacement:   .229 ft^3   x  2 =   .458 ft^3

Total inside box volume with ports and subs displacement =    4.05595 ft^3

Could someone tell me if the "common chamber" is a bad idea or not?  I keep hearing that you should seperate the chambers in case one blows.  However, WINISD says that you will get more SPL from using the "common chamber."  I would like to know the pros and cons of both methods if anyone knows them.  Will the "common chamber" cause my speakers harm?  This will be my first attempt at building a box for subs.  As a matter of fact, these Kenwoods are my first 2 subs period.    I also would like to know if I should use bracing for this 4.05 ft^3 box?  I have read that you should use 2 baffle boards and glue and screw them together for a sturdier box, if you do not brace it inside, and if you brace it inside, you should use a coulple 2" x 2" boards and glue and screw them along a couple of the seams on the inside.  Could someone tell me how to figure out how much volume either of these methods would take up, if I even need to do one of them? 

Here is a copy of the owner's manual:

http://akamaipix.crutchfield.com/Manuals/113/113W2511.PDF

These 2 subs are being pushed at 400 watts RMS each.  I have a Dodge Intrepid.

  I am really glad I can get help from this forum.  Thanks!

Sorry, I forgot to ask about port placement.  I know you should place the ports in the same direction as the woofers are firing, but does it matter where on the baffle board you should put them?  For instance, is it better to put both ports in the middle, or put the woofers close together and put the ports on opposite sides of each woofer?  Also, do the ports have to be a port diameter's length away from each other like they have to be away from a wall of the enclosure?

Thanks.