I am looking to move my subwoofer from a sealed 0.5cf enclosure to an approximately 1.45cf ported enclosure. While I have a pair of subs, using WinISD a pair sealed is -3dB at 45Hz, while a single in a ported enclosure at -3dB is 32.5Hz, using 2 round ports 2" in diameter and 16.85" long. However, I have never put together a ported enclosure before and have some questions about port placement, along with clearance on a down firing sub. The enclosure will be built to fit inside this:
It will be cut at an angle to fit flush against the back seat, ideally giving the illusion when looking in from the outside that it is a suitcase sitting there. So, my first issue is wanting to keep this stealthy while also figuring out somewhere to put 2 x 2" holes for the ports. The xmax on the sub is 9.5mm so I am hoping to get away with 1.5-2" of clearance, however I have read that if the port is too close to the floor, that it (the floor) can have an effect on the port. The problem is if I have the enclosure floating too far off the floor, then it takes away the entire purpose of the stealth look. Assuming 1.5-2" of clearance is OK, is it fine to have the ports on the same face of the enclosure as the subwoofer itself?
I was also thinking, in my trunk there is essentially a factory false floor that provides about 2" of height above the actual trunk floor. Currently my amps and DSP are in that location, but once I move the subwoofer then those would also move. You can see the space I am talking about here:
Essentially a wooden shelf sits on top of this, you can see the lip the shelf sits in on either side. My thinking is of cutting an opening into this wooden shelf, to have the sub then firing down into this opening and also to have the ports facing down into this opening and firing into the same space.
The suitcase would be mounted to some brackets or something that is attached to the floor, but from the outside would then appear as though it is sitting directly on the trunk floor (hope that makes sense).
With this idea am I going to run into problems? either with the sub firing down into there or with the ports firing down into there? If not it should really help with trying to disguise the ports and also with having enough room for the sub to down fire.
The only thing then is finding a spare floor for the trunk outside of paying Audi over $350 for a piece of wood with some carpet over it!! Before anyone mentions it, if I had a black trunk, I would just make my own. I have a tan interior though and have so far found no carpet to match out of who knows how many samples. I may still make my own piece and cover it in matching vinyl, hopefully, I can find a color match on the vinyl and it at least saves me having to cut into the factory panel.
Thoughts? Would this work? or if I fire the ports and subwoofer down into that location am I going to be running into a ton of problems. Worst comes to worst I will run the pair sealed, but am really hoping to figure out the ported enclosure.
Thanks.