I am planning on porting my Diamond Audio D615D2's (T/S Parameters). This will be for a daily driver so I wanted to tune as low as possible. I have made an initial design:

 

Maximum external dimensions are 46" long by 14" deep by 16" tall.
I believe it would be tuned to 32hz with the port 25" long and having 43"^2 of cross area.
Hopefully some fibrefill and possibly inverse mounting the subs will lower the tuning frequency a bit.

Here are my questions:

1) Should I have the vent on axis with the subs? The subs will be rear firing in my trunk behind the backseats.

2) Should I use the snaking vent in the example or a L vent which runs along the back wall?

3) Is there any benift to having two 1.5" vents on each side, as opposed to a single 3" vent, if the tuning frequency remains the same?

4) Will the 15Hz subsonic filter on my amp be sufficent protection against driver unloading or do I have to raise it to 30Hz?

Any other suggestions are also appreciated.

 

1. yes.
2. I prefer the L but the labrynth is ok.
3. Technically yes but it's not a big deal.
4. Try both out.

 

Thanks for your reply. I have decided to go with the L port and extend the port a few more inches to further reduce the tuning frequency.

My biggest problem now is that the box is only 16" tall and I have to put two 15" subs in it... I am planning on cutting out the driver holes after assembly but i think they will be too close to the top and bottom for T-Nuts...

One other question: If I don't inverse mount the drivers, will it be too close to the port? They have a mounting depth of just over 7" giving me only 3" of space to the wall...

 

Bump for help.

 

you should have no problem with the t-nuts except possibly the top and bottom holes(use a heavy duty screw there if you have to). The distance is not a problem at all, mine only has .5-.75" clearance. By the way, that nice simple design should yield you some A class bass.