well after a lot of thinking as much as i hate doing fiberglass the only way i can see to get 1 cu ft of airspace in the back seat of an access cab and cover up the holes left by the factory amp i came up with this enclosure. it looks a lot like the subx enclosures but is very different in many ways.
first of all after 20 years in the car audio industry and hundreds of sub enclosures later i just don't take the easy way out of anything! sealed enclosures are for ammatures! so i never build them anymore.. unless it's ported and tuned for the vehicle and the music that will be played on it i won't waste any of my time building it.
besides i can get easily the bass of a pair of 12's out of a single 10 if its designed correctly. so here is what i have so far. this is a custom made sub enclosure that will hold a Alpine PDX-5 amp in the top section. as you can see the subwoofer will be fireing into the back and floor of the cab. this is optimal because it totally eliminates phase cancellation. this is because the sound waves have to travel the entire length of the passenger compartment before folding back on itself at the dash.
any time you locate a sub forward of this position you will have a dead spot especially near the origination source. with this design its eliminated.
additionally you can't see the ports but on the pic of the underside there are going to be 2 2" ports that also fire into the same location as the sub. i had to use 2 smaller ports rather than a larger 3 inch because of limited space on the driver board.
in addition to this box when finished i plan to dynamat the entire rear wall of the cab behind the seats, i hear most of the road noise from back there and also plan to dynamat both inner and outer skin of the rear doors and front doors.
the alpine amp is a 5 channel unit that will fit perfectly in the top of my amp rack its about 8 inches tall, 10.5 inches wide and 2 inches thick it has 75x4 and 300 x 1 watts output its the only amp small enough to fit in this location. it also generates almost no heat so i dont need to worry about ventellation. also an added bonus is it has a blue light that will be approximatly in the same location as the stock sub had.
i also plan to make my own custom rear door speaker grills to accent the stock interior color. more on that later.
in the mean time here are some pics as to the progress i have made so far.
as for the sub i have my own subwoofers i had designed years ago when i invented a sub enclosure called a Power Mouse. these subs are rated for 650 watts RMS they have 3" diameter coils and 18 lb magnet's they have a 2" peak to peak cone travel and the tensil leads are woven into the spiders so they dont slap the cone, they have dual spiders and rubber surrounds. they are optimally configured for ported enclosures.