Recently purchased 2 GNX104's, need box plans (new to car audio)

S0CalS0L

Hi, I just recently picked up a pair of GNX104's on sale at fry's. I'm going to be building a box for this pretty soon, i tried looking for the box plans in the "toolbox" section but i wasnt able to find any for 2 GNX104's in a ported box. I'm pretty new to the whole Car audio scene, and this is my first ever Polk purchase (actually it's my first ever subwoofer purchase :rolleyes: ). Any help is appreciated, thanks.

MacLeod

There will probably be plans for a sealed box. Most Polk Audio subs worked best in a sealed enclosure. Sealed boxes are better anyway. They sound better, can handle better power, are more forgiving of design flaws, are easier to build and so on.

S0CalS0L

The thing is i have someone that has already built subboxes before, but we would like to find dimensions suited for this box. I'd really like to build a ported box if that's possible.

exalted512

try calling polk
-Cody

LittleCar_w/12s

I know it's a bit off topic... but what was your opinion of the Fry's audio showroom, etc? the one here in houston is absolutely crappy, and the home system rooms are worse. I was ashamed to have Polk stuff in there... they even have an entire room here dedicated to Polk home audio, but I'd never be able to figure out what I'm listening to or where... I used to work there, and they say SoCal store is the best one, I was just wondering.

Anyway, I'd use sealed if you want to listen to music, and ported only if you are so insanely beguiled by getting SPL ratings that you think you need it. The only other reason to use ported is to superfinely tune your subs for a perfect flat output at high SPL, but after all the time and effort of doing that and building the proper equalizers you just as well should go with the sealed and lose a few DB's to keep the quality.
-Jerry

S0CalS0L

We have two fry's in SoCal (San Diego county). The Fry's closest to me has a crappy sound room, the subs they have there arent even hooked up. The other Fry's In rancho bernardo has a NICE sound room (2 actually if you count the car video room a sound room to). The fry's itself in rancho bernardo is pretty cool to, it has an underwater Atlantis theme with a bunch of huge aquariums around the store.

Well enough about Fry's, the main reason why i want a ported is is for more bass. I have a honda del sol, and if you dont know, the Del sol has a fully seperate trunk and passenger compartment. The trunk and the passenger compartment are divided by a metal wall, glass from back window, and another metal wall. That's why i wanted a ported box so i can have more bass.

MacLeod

A ported box will give you more bass but not that much. The difference will usually be no more than a few decibels.

However if youre sold on the ported box then I agree with Cody in that you should call Polk. They will be able to hook you up.

Systems

Originally posted by LittleCar_w/12s
Anyway, I'd use sealed if you want to listen to music, and ported only if you are so insanely beguiled by getting SPL ratings that you think you need it. The only other reason to use ported is to superfinely tune your subs for a perfect flat output at high SPL, but after all the time and effort of doing that and building the proper equalizers you just as well should go with the sealed and lose a few DB's to keep the quality.
-Jerry

HAHA.....obviously you've heard a **** ported box tuned to a insanely high freq.

Ported sounds VERY nice with many subs.....just tune low, around 25-30hz.

Not very hard to make, quite simple. Extra 3db too

There not momo's either(hehe)

neomagus00

well, since he's getting the box built by someone that sounds like they have the experience necessary to build a ported box, that bit is no big deal (yeah, it isn't that hard, but better safe and happy than sorry and angry, yes?).

that extra 3dB can help, yah, if it's put in the right place for the vehicle and if a subsonic filter is used. i think that many people are soured on vented boxes because they've heard too many badly-done examples...

lastly, to socal, if vented is your thing, you got the right polk sub... and if you dont want to call polk i have nothing much to do right now so i could probably cook up a design (it's probably best to call polk tho...)

S0CalS0L

Hey thanks for all the reply's, i really appreciate the help. Me and the person who is going to help me build the box originally planned on making it a ported one. I'll be sure to e-mail Polk soon to get the plans. Thanks again on all the help, glad i was able to get a decent sub for such a great price. Thanks again!

S0CalS0L

Well i e-mailed polk and haven't recieved a reply yet, but i was wondering if this box would work. These plans are for the GNX104's but for a single ported and a single bandpass. Is it possible to just build a box by doubling the length dimensions and just putting a divider inside the box so it's like two seperate boxes?

here's a link to the two boxes:

Single ported:
http://www.polkaudio.com/car/toolbox/subboxplans/subbox_plan.php?id=17&mesurements=standard

single bandpass:
http://www.polkaudio.com/car/toolbox/subboxplans/subbox_plan.php?id=27&mesurements=standard

one last question, for the single ported box there are two different enclosures, one thats 1.25 and 1.00 cubic feet. What's the differents besides the cubic size??? Does the more cubix feet mean more bass??? Thanks again!!!!

neomagus00

the bigger box should give better response, the smaller just existing for those strapped for space

it's probably best if you designed your own box; use 3/4" MDF (medium density fiberboard) and a single port eight (8) inches in length by three (3) inches in diameter; the total interior volume should be 1.25 cubic feet (2160 cubic inches) WITHOUT including the port... so since there's about 51 cubic inches taken up by the 7-1/4" of the port that's inside the box, the total volume needs to be about 2211 cubic inches; then you put the port in that.

designing your own box allows you to use the space you have most effectively, leaving maximum cargo room and just generally getting the subs the hell out of the way. note that in your box design you have to account for the depth of the sub (in this case, it'll stick just over four inches into the box), so the box'll have to be at least five inches deep inside. also note that the port is 8 inches long, so 7-1/4" are inside the box, and the end of that port can't be within one port diameter - namely 3 inches - of any wall; so if you put it on the front of the box, the thing has to be at least ~10" deep.

S0CalS0L

Thanks for the help Neomagus, i just got an e-mail from polk, i e-mailed back with some dimensions of my trunk, hopefully that will be enough for them to help me out with the box plans. Thanks again to everyone who gave input and help.

Airplay355

unless u plan on listenening to organ music in your car, why would u need a subsonic filter?

exalted512

when porting subs, it is necessary to use a subsonic filter or you run the risk of blowing the subs
-Cody

Airplay355

why? subs dotn play subsonic unless they are fed subsonic frequencies

neomagus00

true, but in this case a subsonic filter simply means a highpass set to a very low frequency, not literally 'sub-sonic'. since a subwoofer sees approximately no support from the air in a vented box below the tuning frequency, it flaps around madly; thus, put on a highpass at the tuning frequency and you don't have to worry about over-extending your sub.