View Full Version : NEED HELP 2 18" RE SX 18s in 89 Caprice

03-13-2010, 01:33 AM
I got a box design from Greg from USAmps/RE but he told me he recommends 20 CU FT

but the design he gave me is for 9 CU FT and im pretty sure i can fit more then that in the trunk..its HUGE

anyone have any idea how big of a box i can fit in the trunk..ported..tuned to 33hz preferably


any help?

he also said the 15" was a typo and thats the specs for the 18's

03-13-2010, 01:48 AM
Well that design is for a pair of their 15's, apparently. To do the SX's right you need around 6ft^3 each after displacements. So around 15ft^3 overall...check your trunk and see is you have the space for that.

03-13-2010, 02:05 AM
yea what ryan said, and thats on the small side too but will be suffice. the optimum is 8 cubes @33hz for 1 18sx. so 16 cubes plus port. maybe greg was giving you a design and not specific to your subs or he sent you the wrong info.

03-13-2010, 02:28 AM
thats what im thinking is wrong info

how can i measure my trunk to figure out how to design the box..im new to building a box.im used to getting one of my buddies systems and just hooking it up..

03-13-2010, 03:46 AM
measure your trunk to find out the maximum size of the complete box. probably will have to build the box into the trunk. not going to be able to build it then install it. may be a little complex for you being you never built one. see if there is someone on here local to you that has experience to help you would be your best bet. offer them an incentive like a little $ and maybe some beers.

justin smith
03-13-2010, 03:57 AM
wall it

03-13-2010, 08:04 AM
and thats on the small side too but will be suffice. the optimum is 8 cubes @33hz for 1 18sx. so 16 cubes plus port.

Very true, those SX's like larger boxes from what I've heard.

03-13-2010, 01:07 PM
Greg jus emailed me tha same specs for my SX 15's, My Box slams (if this helps you any) !!!!!!!!!!! - Check out my NEW signature pic on bottom...

Greg wrote: Attached is a box that should do very well for you just shorten the port by 3 inches

Greg Carolus

US Amps - RE Audio Tech Support / Production Manager

20819 Currier RD Suite 100

City of Industry CA 91789


Office 877-267-9360

Fax 909-869-9199

Cell 626-833-2177

[email protected]

03-13-2010, 01:12 PM
so then would his specs that he gave me make a decent sounding box..i dont want to compete..i just want to be loudddd and hit LOWWWW

but for the low i probably need a bigger box lol

03-13-2010, 01:22 PM
dont make the box with that design he sent you, your subs wont fit. its for 15" subs. figure out the math on the heigth which is labeled C 18.5" height and your sub wont fit because of the thickness of the top and bottom boards of the box has to be subtracted from the total height. i would get another design that is actually for your subs and not the 15" ones. or sell the 18s and get 15s cuz the 15s in the correct box will sound better than the 18s in a box that is way too small.

03-13-2010, 01:33 PM
ok..so if i build a bigger box..have them firing up at the trunk and the port firing towards the front of the car..will it get loud or will i just have a ton of rattle?

i want this to hit rediculously low

so i guess imma have to build it in the trunk...this is gonna **** lol

03-13-2010, 01:41 PM
yea its going to rattle lol, even with lots of dynamat etc. you will lose some power if you face subs towards cab in most cases but will lose rattle. if you just want loud i would face subs and port towards rear of car just dont completely block off airflow if you follow. i have two 18s in my 94 deville and there is enuff height room to have the subs face the rear. mine are in sealed box's but you dont have the option for sealed enclosure.

03-14-2010, 06:50 PM
got some pics and some measurements lol






how many cubes do you think i can fit in here?


03-17-2010, 12:37 PM
i would go with 2 15's :(

03-17-2010, 12:42 PM
i would go with 2 15's :(

Yeah, I don't think trying to fit 18"s is worth it but it may be to you. ;)

03-18-2010, 11:47 PM
well im getting a 2001 grand prix 2 door and im thinking about walling it..think its doable for the two 18's?