will porting my rear deck and sub facing into the car at the front of the trunK(by the seats) into the hole in the seat cause cancellation?

 

Not if the subs are in a properly sealed enclosure. For info on sub placement see: http://www.installer.com/tech/aiming.html

 

dude ive read all that stuff b4, IM PORTING not sealed

 

Why did you ask such a stupid question if you already know everything?

 

BUDDY did i say i knew everything... i have read that already and IT DOESNT SAY anything about porting a rear deck... READ my post before u start yapping... porting the rear deck WILL effect the sound and cancellation factor whcih si why i ask i know that if i didnt port my deck i woudl face the subs towards back and have the ports on teh same plane but since the port will be reflecting off glass off back and sub face in it will basically be on the same plane, thsi is the conclusion i came up with...

 

Unless the ports are tuned very high there should not be cancellation. This is because of the long length of low frequency soundwaves. Where you will have cancellation will be with the wave reflectiong off the back of the trunk. By the time the wave gets back to where the front wave exits the box, there is enough distace for a half wavelength. Which would be similar to haveing two subs out of phase, but only at some frequencies. But more than likely there will be varying degrees of cancellation in a broad spectrum of the frequencies the sub plays.

A 60 hz wavelength at sea level at standard temperature is 18.8 ft. Half a wavelength is 9.4 ft. So this frequency would most likely not be totally cancelled. If the distance from the front of the trunk to the rear is roughly 42 inches, or 3.5 ft, the wavelength that would be totally cancelled would be 14 ft long. Which is twice the distance from the front to the rear of the trunk. So about 81 Hz. But like I indicated before, all frequencies would be affected to some extent. And it's probably a couple more inches from front to rear of the trunk.