Ok, first off I wanna appologize for being so FINICKY about everything but I was gettin ready to order my amp and after doing more research (if im understanding this correctly) after bridging the amp Im getting (Mbquart FX4.100) ill be looking at 400Wx 2 channels...does this mean Ill only have 200 goin to the sub?(earlier in this post I stated I wanted to do a 4 channel amp, 2 channels goin to front components and bridge the other 2 for the sub) the subs RMS rating is 250w...this wont be enough will it? Trying to stay away from having to run multiple amps bc my truck already has a run of 8 guage wire and being Im TRYING to cut corners with costs Id like to keep it that way BUT if I have to run multiple amps Id do it all...again I applogize and seem to overthink EVERYTHING before doin anything ...damn u OCD!!!!

 

Any suggestions?

 

Im not sure...but THINK this was a dumb question...lol

 

im now thinkin about porting this box for the 12 i have (its recomended for sealed enclosure but gonna get another 12 more than likely...any 12 recommended for ported box?) but my question is....ive NEVER ported a box and dont know where to start...i VENTED a box for a 12 in a mustang back in highschool and that thing was nasty but it was built to specifications given to me by a friend who competes...and another question, ported vs vented? I know the difference LITERALLY but what is the difference based on performance?

 

Okay first off the 400x2 means each channel will see 400 a piece.

Second no difference really, ports are round and vents are square or rectangle that's about it. Depending on ease of install really decides which one you go with. Round port's for smaller enclosures (less than like 1.5-2cf or so) tend to have to be really long where they won't work with space requirements without using very small ports (under 4") that end up creating bad port noise and chuffing. For slot ports or square ones (I'd reccommend slot over square, a lot easier to build) they generally don't need to be as long as a round port because they have more port area in them. Again though if you make them too small you can have port noise. A general rule is at least a 1" wide port for low power boxes (around 3-500 watts), if your planning on running two subs then I'd at least go with a 1.5" wide port. Also the general rule is every 2" wide the port is it should be 5-7" tall.

So you'll need to figure out what airspace you need for the subs after displacement and then the tuning frequency. 34hz is generally the magic number for low bass, but you can tune higher if you want it to be for more rock music, however if you tune too high and play a song with real low bass it can unload the sub (it'll act as if the sub is working free air) and can damage the sub. Once you have the tuning frequency you can plug it in into a online calculator to figure out how long you need it to be.

Also make sure the port opening is not directly behind the sub, keep it off to the side of it. And on the outside of the box if it's a round port leave at least the diameter of the port of space in between the opening of it and any other surface. If it's a slot at least around 1.5-2 times the width of the shortest part of it (i.e. a 2x5" port leave 4" of space).

 

IF i go this route, itll probably be vented being ive done it before...the thing is, if i do this I suspect i will have to downfire this and would that be a problem?...i mean i dont know for sure but does the vent need to face whichever way the sub faces or is there a way around this, like have the speaker downfire with the vent facing toward the front (all this under the rear seat) ?

 

Nope, vent can face any direction just make sure you give it room to breathe. And downfiring the sub would be best it'll sound louder than if you did it firing towards you, but again don't forget to give room for the sub to move.

 

by room to breathe u mean...enough space between the back of the speaker and the vent on the inside?

 

Room to breathe I mean space between the vent on the outside of the box and anything else, at least a 1/2" between the magnet of the sub and a solid wall on the box, and at least about 1.5" between the front of the sub and the carpet on the floor.

Don't have the vent opening that's inside the box directly behind the sub, try to get it at least the diameter of the port away from the sub also.