View Full Version : Up or down firing?

09-12-2003, 10:10 AM
I have a 2001 GMC SIerra Z71 extended cab truck.

I have built 2 sealed boxes, 1 each, for 2 CDT MS-80 8" SQ subs. The boxes are .42 cu/ft and the spec is for between .25 and .45 cu/ft.

The subs will be going under the rear seat of the truck. I will have between 1 and 1.5 inches of clearance between the top of the box and the bottom of the seat.

Will I get better results by having them fire into the seat or off of the floor?

Will walling off 3 sides and leaving only the front side for the soundwave to generate forward help?

Any and all help is appreciated in advance.


09-12-2003, 05:03 PM
fire them down. thats what i was told to do. give about two inches between the sub and the floor, and leave one side open on the bottom so the air can move out. i did this in my 99 ext. cab and it worked out pretty good.

09-13-2003, 12:53 AM
what to u think about having them fire towards the front? thats what alot of people do. look up HLLRZR13 in the photo gallery. if u can get that to work then i recommend that.


theres a link

09-13-2003, 01:20 AM
i dont know if i'd want to do that if you have anyone sitting in your back seat. i put mine behind the drivers side, to where it would be opposite of the third door, so people would usually only sit behind it if i had many people in my truck. i hardly ever have too many people in it, and there are black scuffs all over my box from shoes and stuff. i imagine if i had the sub firing out, my passengers would be careful and try not to touch it, but either way, i think that unless you're extremely careful something will eventually happen and damage your sub