New install

[Kent C]

I just redid my box, actually I was running 4 10's free air. I got a deal on 4 new subs built a box and when first listening it sounded pretty good a little more bass than the free air setup but not much. Then I opened the trunk and WOW the bass seemed to triple. With the trunk open the car sounds amazing, close it and its like I just unhooked 3 subs!!! The box has 4 10's with just over 1 cubic foot per and are ported. any recommendations as to why or how to fix! the subs are rear facing if that matters at all.

 

[6APPEAL]

Most of your subs energy is being used to vibrate the metal in the trunk area instead of being used to make sound pressure. A Dynamat trunk kit will fix that.

 

[HYBRIDT]

Actually, what you've got going on is a standing wave or wave cancellation issue and it is one of the hardest issues I've ever had to deal with in my 12 year professional custom stereo career. What's happening is the wave from the enclosure is bouncing around the trunk and cancelling itself out, when you open the trunk you give the wave somewhere to go and the effect of the minimized cancellation is SUBSTANTIALLY increased output in the car. Sometimes it can be resolved with placement of subs (try pointing the subs another direction or moving the box to another part of the trunk, sometimes firing the woofers down and spacing the box up off of the floor works) and sometimes you actually have to electrically shift the wave. 180* shifting (flipping the wires) won't get you any better results, you need to use a passive network (which eats power) or sometimes you can mechanically shift the wave by porting/venting the enclosure. As a last resort you can press the enclosure right up to the rear seat area and COMPLETELY seal the face of the box to the cabin area. The two areas have to be sealed from each other, like behind the quarter panel/rear seat area and above the headliner. I hope this helps make it a little more understandable and good luck.

Adam

P.s. cutting a series of holes behind the taillights to vent the air won't help either. I didn't do it, but don't ask how I know.

 

[marred4life]

Ide Try Porting Your Car, Where Your Rear Speakers Site, Make Two Ports Between The Speakers To Bounce The Wave Into Your Interior