View Full Version : Box Build for 2x Pioneer 12's
08-11-2009, 10:42 PM
Hello everyone, this is my first shot at designing and building an enclosure. I have 2 TS-W1207D4s which are 400w rms.
Current set up:
The box is probably giving about .75 foot^3 per sub...
This is what I have done so far... Please make any comments if you see a mistake I'm not too experienced with BassBox Pro.
Box should come out to about 40" wide 16" high and 15" deep
tuned to about 33.5 hz with a 2.25 inch wide port that runs 11 inches into box. Does it matter if the box does not have a second piece that creates a whole L for hte port?
This graph shows roughly comparison of new box to old box. The new ported box is in orange... old in green.
08-12-2009, 12:26 AM
According to my math and your dimensions that box is 4.02cf internal not including the port.
As long as the box is deep enough to accomodate the legnth of the port + at least the width of the port away from the back wall then there's no need to have an ell. IOW, if your port is 11"L and 2.25"W you need at least 13.25" of depth to avoid the need for the ell. Any less and you would have to have it.
08-12-2009, 12:53 AM
Thanks for the reply. The box comes out to 15 inches deep so 13.5 inches minus 3/4" mdf on both sides. So it should have almost a perfect clearance.
Does bassbox pro put into account the port displacement before it graphs the results?
08-12-2009, 01:05 AM
NP. The tuning may likely be a tad lower than 33.5. The port wall is almost the same distance from the back wall as the width of the port. It's possible that the area between the back wall and the end of the port may act as part of the total port legnth, thereby theoretically legnthening the effective port legnth to somewhere around 13.25-14". You can remedy this by decreasing the width and increasing the depth.
08-12-2009, 01:11 AM
Thanks... well should I just build it the way it is or would you close the port and lengthen it a little?
08-12-2009, 01:16 AM
It won't hurt anything to build as is, worst case is you get a little lower tuning freq. Probably won't even be audible and not low enough to cause any functionality problems that I can tell.
08-12-2009, 02:30 AM
Thanks for the response, I'm gonna cut the sheets tomorrow hopefully and I'll post pics.
12-01-2009, 12:07 AM
Took a while to getting around to constructing this.
Question: How necessary is the 45 before the port. The area which the 45 degrees will not fall within the "port volume" correct??
When I designed the box I did not include the 45 in the displacement of box volume, or port volume, thinking it was part of box volume and would be negligible.
Picture of 45 in question
Another question: Will liquid nails be fine for the seal on the corners or should I shave off what I used to seal and replace it with silicone?
12-01-2009, 12:26 AM
liquid nails for sealing is fine, for gluing, no.
12-01-2009, 12:34 AM
why not for gluing? what would you recommend?
12-01-2009, 01:56 AM
Any answer on the 45? Also if I put in the 45, should the measurement from the corner of the port wall to the middle of the 45 be equal to the port width? Obviously using a 45 instead of a quartercircle with radius of 2.25" is going to result in parts that are wider than 2.25"... thoughts?
12-01-2009, 09:50 AM
why do people use liquid nails? proper wood glue, screws or nails, seal with good caulking - - liquid nails smells real bad, and takes forever to get the smell out of your car!
plus you can pull it apart! (also heard the vapors affect foam surrounds, dont know it to be true but it has been said)
12-01-2009, 11:30 AM
Well it's my first box build, but I appreciate the constructive criticism. I've let the liquidnails dry in every junction for 24hours, so unless vapors form from the pressure they're under during the woofer operation, I don't see a problem.
If someone could comment on the 45 I would appreciate it. A table saw with a tiltable blade isn't exactly accessible in my apartment.
12-03-2009, 02:10 AM
Well I'll be cutting the 45 on friday and it should hopefully be put together by the end of the weekend. I appreciate the suggestions so far and if at all hopefully someone atleast got a design or few ideas from this. I'll post progress pics when finished and a video if anyone is curious.
12-07-2009, 04:03 AM
It's been raining, so the build has been delayed.
12-07-2009, 03:01 PM
woah, did you just say the box is 4.0 cubes, put your port area is just shy of 33 sq in?
even w/ sub displ
you still have about 3.7 cubes w/ less then 9sq in of port per cube
That port is WAY too small for that box
12-10-2009, 01:59 AM
Okay, then why is bass box pro showing barely ANY difference if I reduce the box volume, or increase the port length, by a reasonable amount. I appreciate your criticism, I'm just failing to find it helpful when you are giving no explanation as to why or how it's going to affect the tuning.
I have 2 pioneer TS-W307D4 in the box. Put the parameters into bassbox pro and you'll see what I mean. I admit the first post is incorrect, because the box volume is smaller and I don't know how I ****ed up the calculations.
If you know something I don't, then, by all means explain.
12-10-2009, 07:04 PM
ProjectP is referring to the common rule of thumb, "16 sq in of port area, for each cubic foot of internal volume"
This is a good estimate of what's necessary to prevent port noise and maximize the output of your subs.
Since you're running a low power setup, and it's a trunk car... you'll be fine with your designed system. It just may not have the "optimal" level of output.
If it were me, I'd cut an inch or two off the baffle, to shrink the internal volume and increase port area. Assuming the box is ~16" tall, you'll want around 3-4" of width for your port... this would also require you to increase the port length along the back of the box.
12-10-2009, 07:23 PM
Port is on the small side, and that bend in the port *could* potentially be problematic. In a trunk, I doubt you'll hear any port noise, and it will certainly be an improvement over your old box. However, there is plenty of room for improvement.
I've had experience with those subs. Hit me up if you'd like help designing a new box or anything.