box design for dual SA 15's
 

Hello all, this is my first time ever using a forum of any kind and hope im doing this right. I just purchased 2 SA 15's and need a really good box design to fit an '98 Accord Coupe. Looking to go ported and tune around 28Hz. Trunk is big but shaped funny and need to net 6 cubes to achieve decent results. Thanking in advance to all who can help.

I need trunk measurements at the cabin-trunk opening, the largest amount of surface area possible, squared/rectangled IE if you can fit either 30x15 or 28 x 18, the 28x18 should have more surface area and thus more available space. 6 NET will be a squeeze. This is why most people use 12's for small car trunks. Those SAs dont need a huge box, Im pretty sure SA recommends 3-4 cubes but you will get better results with bigger space (99% of the time). A port will take up roughly 1.5 cubic feet for that tuning. 28 hz is very low, and the port needs to be longer as tuning lowers. Youll want to use .75" MDF and a 1.5" baffle (the face the subs are mounted on). Also 45 degree corners and resin in the corners and use rabbit joints (interlocking corners). If you cant do this yourself than find a shop with a CNC lathe. I can give you a piece by piece cut sheet, however, if you measure wrong than youre up poo creek. My box was all CNCd and its SO clean, measured perfectly down to like .000". I got my 2 18s in 8 cubes sealed on 2500w working a couple hours ago XD.

Dont use a sealed box.

Also look into getting the "big 3" electrical upgrade, where all the ground and amp to batt wires become 1/0 gauge (the largest, some are over sized though), an alternator upgrade (like +100 amps IE if your stock alt is 100 than youll want a 200A alternator that makes its power at an early RPM) and 1-2 deep cycle batteries ("group 31").

Wow!! That was a great response, thanks and congrats on gettin your system runnin, i bet it BANGS! All electrical upgrades already done except for the alt which will have to wait till after xmas. From the back seat coming forward towards the trunk hinges i got exactly 32x16 and from there furthertowards trunk opening max i can go is 41x18 and these are the ext dims i have to work with. Cut by cut would be great or a design in which i can take to have some one build as I've always done before. Any additional info needed lemme know...

Oh yeah.... dims are in inches just W and H. Depth from back seat to furthest point toward trunk opening is 24" and if necessary can push to 26"

With 41 left to right, 18 height and 24 deep its 8.2 net before displacements. If you can fit that through the interior trunk opening than youll net atleast 3.5 cubes per sub after all displacements. Make it as big as possible on the left-right & trunk height, decide depth for yourself cuz you may want some space between the subs and back of the rear seat, unless you plan to only play them with the rear seat folded down.

I drive with the seats down 95% of the time unless my children are with me. Im not sure how to calculate port and tuning with the box having 2 differnent heights. If you could put something together on paper for me, i would not be against paying you for the design. Local shops around here are lazy and and in my opinion, dont really care about what i want but more into makin life easy for them.

I know it all too well. I didnt realize until 2 months ago the best shop near me is 10 minutes away. If youre near a big city there will probably be competitors and many of them need help. Find the shops they go to. Where are you? You dont need to pay me. I do this because im addicted. Itll take about 10 minutes to calculate everything and do a cut sheet. I use the12volt.com port calculator. You cant just type in numbers because you need to do a few maths on paper, some calcs do & dont tell you that they account for other variables and may throw tuning off.

41 x 18 x 24 or 26 external, right?

Music preference?

Sub amp?

Taken a few hours ago.

https://www.youtube.com/watch?v=lv-9...e_gdata_player

Great vid man.... Looks pretty damn sick! Was running 3 lvl2 12's on that same xtx before going back to 15's. Perhapse we are at a missunderstanding about the dims and shape of this box. Basically, the rear of the box has to fit between my wheel wells and usable space for that is 32x16 with 11" depth. From that point, we can use 41x18 with an additional 13-14" of depth for the front half of the box. My apologies if i confused you. With this particular shape, I am able to use more areaas well as preserve some at the same time. Was thinking aero's may be a better option due to the shape. Listen to a good blend of everything but primarily reggea, hip hop and dubstep. Comin to you from brampton Ont. Sub amp is temporary and posted for sale as i will be upgrading in a couple weeks.... Currently using a Sundown Audio SAE-1200d v2.

Gota wait till im at my friends for net. Cant do it with mobile.