SP4 box flex, need help.

[ncc74656]

so i built the box and i feel that perhaps the port is to large or im not giving it enough power. the sound feel lacking in the punch. now having said this the box also have flex. it has double baffle front and 1" dowels connected the bottom of port to bottom of box, front of box to rear of box, and side to side. HOWEVER the top of the port is flexing a good 1/4 of an inch and the sides are still moving about 1/8".

i think i will double the sides up and add another piece on top? what should i brace to remove this rattle and flex?

also the sub is on a ZX2500.1 and the sub is in no way moving to its xmax and its getting crazy hot! my BL i never felt due to it being a rear firing box. the sub at 1/2 volume level on my HU gets almost to the point of burning my hand when i touch the dust cap. is this normal? the sub has been played for about 20min and the box is 4 hours old.

http://imgur.com/a/OeTpd

[Amart88]

I would definitely add a brace to the inside of the port. Box flex is bad!. I would cut a piece of mdf to glue in the middle of the port to ease the flex. and roundover the edges of the brace piece to reduce any port noise.

EDIT: Or you could try adding anothey layer of mdf to the top.

[ncc74656]

i will do both. now this will take up space in the port so how do i make it not have port noise? should it be the full length of the port or back to teh wall? how much will this effect tuning?

[Amart88]

i will do both. now this will take up space in the port so how do i make it not have port noise? should it be the full length of the port or back to teh wall? how much will this effect tuning?

You don't want to go the whole length of the port. The smaller the brace the less it will effect tuning. It would slightly reduce your port area. Personally I would try doubling up the top first and see what happens. Also, you could use wooden dowels in the port instead of mdf.

[ncc74656]

i will place a 1" dowel i the center of the port and double the top. i also had to change my build dimensions and do some off hand calculations. this threw my box from 7.1 cubic to 7.6 cubic. i think i may remove the sub and place stripes of MDF say maybe 5" wide on the back and sides to take up air space back down to 7.2 or so. what do you think?

[Joe X]

Set your subsonic filter to 28-30Hz, likely that will help with the overheating, that along with proper electrical and gain settings.

[ncc74656]

I set the gain by ear, playing a 40 herT tune waiting until I heard a difference and then pulling it back a bit. The subsonic is currently at 26, I'll turn that up.

[ncc74656]

I set the gain by ear, playing a 40 herT tune waiting until I heard a difference and then pulling it back a bit. The subsonic is currently at 26, I'll turn that up.

[01 S-10]

Your most likely clipping the hell out of it, make sure bass boost is at 0

Also I would try all thread instead of the dowel rods

[Nivram]

glass and matte it. port bracing and maybe some threaded rod to replace the dowel rod