In my Iroc, i have a Rocksford Fotsgate 100 Watt at 4 ohm amplifier, next to it in a Q-Logic .33 CuFt box, i have an old style stage 1 10" sub. The box is a truck box and is slightly taller on one end. When laid so that the angle of the sub in the box is paralell to the rear hatch window, It is much easier to get more volume and clarity than normaly achievable from the combo. I did this one day out of a need for room for groceries and notices an imediate difference. I asked my friend whom owns an Audio install shope and he said somthing about acoustics and what not. All of which made no sence to me.
Even though the brands might differ, if you use the sound waves to make the rear hach reverberate at the same freq. You get tons of good quality sound, little weight and little strain on your amp, and little sound oustside the vehicle.
Make sure that you tune your amplifier with the hatch closed. With it open, it will sound completely different.
Geed luck!

 

It's not making the hatch "reverberate" as you said. Any kind of reverberation is pure distortion and sounds like ***.

What you're experiencing is a situation that's reducing destructive out of phase waves within the car, which is a pretty well known situation. We've had a great deal of discussion here over the years, but it's always good for noobs to see it again.

Essentially, the closer to the back of the car you can get the sub, the better the bass will be.

 

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