Ok, I have my sub/box mounted as shown in the pic (no, visibility isn't a problem), and the sub hits really hard....I always pull the hatch cover when I leave the car, and when I went back out, started up the car, and turned up the music, I forgot to draw the hatch cover back in - I immediately noticed something was different, because the bass hit a WHOLE LOT harder. I mean, I immediately went to the deck EQ because I figured I'd changed it by mistake, but no - it was due to the hatch cover. Why the hell would it do that? It boggles my mind??

 

what pic?

 

i only see something splattered on top of the pic

 

oops

 

How do you get the hatch cover over that? if you drop the box in the well firing back wards thats probably your answer as to why its louder. some speaker placments are produce more sound than others

 

NO, it was just louder with the hatch cover over it - the box placement was the same. And the box JUST fits in that position...probably will change it tonight anyways, see how it does.

 

By leaving the hatch cover on you essentially changed the positioning of the sub. Lets assume you have 18" from the speaker until it hits a surface and is reflected. So the sound wave leaves the sub, travels 18" to the back of the car. Some of the sound is absorbed and some of it is reflected. That which is reflected makes its way to the front and to your ears. Now by leaving the hatch cover on you reduced that 18" down to say 4". Now you've done several things. One, the wave now travels a shorter distance before it is reflected. The farther a wave has to travel to a certain point, the quieter it will be when it gets there. This usually is not as important with low frequencies because they can travel much farther, but it may add to the cumulative effect. Two, you changed the angle at which the sound is reflected. This new angle may send more of the sound toward you as opposed to somewhere else inside or outside of the car. Three, you are changing the surface which the sound reflects off of. This new surface may absorb less of the sound and in turn reflect more of it.

There's always the possibility that leaving the cover on helped to fix some problems. For instance, you could have been getting some phase cancellation and effectively adjusting the box's orientation helped cure that.

All in all it means that there is a more efficent way to use your current setup. So you may find that moving the box gets you some pretty impressive results.