RobertMcDonald

So, I made an error when I built the blow through box, it leaked and recieved some water damage. MDF does not like water. After I removed the damaged areas and replaced it with fiberglass, I decided to do something about the leaking. I built a fiber glass topper that is sealed to the bed/cab to prevent water leakage. While its not perfect, it looks pretty good.

Yea, I cut the hole in my cab as large as I dare. Probably made it too large anyways. The hole is 59" x 19", only a couple inches left below the glass. Looks like I have to fiberglass the box, the bed liner isnt sealing it well enough. I will Start with the top and see how that does. Anyone know if I have to use the matt or can I just use resin to seal it?

Thanks for the cudos, its much appreciated. All I see for the most part is people telling me I made an error in calculations or somthing.

The line is ~9 feet long depending on how you count...lol. The box is 28" deep with the line Here is a couple pics of the design. My link My link

Mainly I did 295 because of space, there simply wasnt enough opening to allow for the 125%. I was under the impression that the SD of a 12" woofer was ~76 sq.in, is this wrong?

FIrst off I would like to thank Forevrbumpn for his tutorial, w/o it I probably would not have undertaken this project. So, I decided one day that I wanted to build a T-line for a buddies car, it housed a single 12. Once I was finished with it, installed and listened, I knew right away that I must have one, it sounded amazing and produced tremendous bass for what it was. So, I went to the hardware store and purchased a butt load of glue, screws, and MDF. I started building on Saturday morning at 0600 and had the box installed on Sunday night. It wasnt complete, but it was close. I just had to see what it sounded like so I installed it. Ok, the box is 17 cu.ft with exterior dimensions of 62"w x 33"h x 28"l and houses 4 Skar Audio vvx-12's. The line is 9 feet long making it ~32hz tuned. It is a tri-fold with a port of 5" x 59". Its slightly small, ~20 sq.in. I placed this behemoth in a 06 dodge ram quad cab, but its not in the cab. I cut the bed and cab open and placed the box in the bed. Its a blow through, this way I can still haul my kids around if necessary. Ok, enough with the talk and on with the videos. Sorry I dont have progress pics or vids, I am single minded when it comes to working and normally dont stop until I drop or the project is finsihed. Ok on with the vids.

I thank everyone for racking their brains on my question. I am at work currently and cant upload photos to show what I meant. I attempted my idea and it didnt give me the proper impedance. In the end, I managed to wire it like the original picture, just had to trim the wires down to allow them to fit into the sub terminals. The end result was right at 1 ohm. So, thanks everyone for your help.

Thats correct, then I wire those 4 Ohm subs in parallel making and end result a 1.33 load. Am I mistaken? My problem is how to connect them w/o having to place two wires on the same sub terminal.

No, I will use one main input terminal. I had planned to disassemble one positive and one negative terminal on each sub. Then I will use crimp two eyelets to a short piece of wire and reassemble the pos and neg terminals with the short wire. That will make each sub 4 ohm and leave all 4 spring terminals available for use. Then I had hoped to use the 4 empty spring loaded terminals to connect the subs together to creat 1.33 ohoms. I will try to draw a picture showing what I intend.

I am in the process of rewiring my subs to achieve a 1.3 ohm load as in the following picture. The picture shows that I would have two wires in the same terminal, one input and one ouput leading to the second and third sub. Can I use the other set of terminals for output instead of using the same ones? I think the answer is yes, but I am not sure if it woud effect phase.