zenclosure rear fire vs upfire sound quality?
 

thinking of changing my rear fire box to upfire. i have a dual 10 zenclosure box with two 10w3v3 and it seems like the hatch rattles more than anything. im not getting that good clean pounding sound. im thinking the hatch is just absorbing too much of the sound waves when the hatch is closed since there is barely any room back there. would the upfire even it out? has anyone ever done this and can tell me the difference in sound?

Sometimes, moving the subs or any speakers for that matter changes/remove standing waves that would cause coloured quality. That said, I would highly doubt that your hatch is 'absorbing' much unless you have a bunch of carpet or cotton or sound absorbing materials in there. I would first check both speakers' polarity, loose mounting, adding sound deadening materials to the panels and hatch to eliminate the noted rattles. Additionally, make sure it is properly filtered with the x-over and driven by good clean power.

There are too many variables without knowing your whole set up, music, volume you are listening to, etc but I would think if you were to add sound deadening and have it properly powered and adjusted, it would make a whole world of difference in comparison to simply moving the sub since subharmonic frequencies are much larger than any car interior to begin with which translates to you already in the sound field. Moving the angle or source at these frequency rarely make a difference with the noted above exception. BTW, the there something call corner loading which works on the principal of horns. Having a sound source at a corner can enhance lower frequency. The Z hatch will aid this to some degree.

sorry I meant that the hatch is taking too much of the sound waves with it being so tight back there. Every little bass note will just sound like a rattle. You're right maybe I just need some dynamat or something in the hatch. The subs are hooked up to a 1000 watt amp @ 2ohm. Low passed at 80 Hz.

I have two up firing 12s and it is overwhelming. Really boom-tastic. I had a few hatch panel vibrations that were cured with felt tape.

Since I'm too lazy to calculate the wavelength here is a handy calculator for finding the wavelength of any frequency, Zakimak made me remember how long a 40 Hz wave is.

Wavelength

Enjoy!