ported box

Yeah that gave me some ideas thanks

But that doesn't give port dimensions as well...

There is another question that wasn't asked... Are you looking for competition SPL or street bass SPL? Many sanctioned competitions measure SPL at around 70Hz but most people are looking to impress and slam their audience with deep tones, ie Street Bass at 30-40Hz. Kicker makes their own boxes and they are tuned to Street Bass.

From WinISD, I got 6cf tuned at 28.6Hz with a round 4" port 4" deep (flare on the outside end) will give you a 4.2dB boost at 59Hz... at 70Hz you'll get about a 3.9dB boost. Shortening the port 1" will jump the 70Hz to 4.2dB and peak 4.6dB at 57Hz but your response curve will sharpen a bit hurting the Sweep Measure (not often measured but for some people it matters)

I tried to get results for a big boost at 70Hz, but I keep getting errors returned. I end up with a really, really sharp curve that is very narrow. But it says that you'll get a 15dB boost. It would seem that the L7 has trouble with it (or the program can't fingure out the Qs for it at 70Hz) >.<

Well I hope this helps give better details for you

Ganbatte ne!

Forgive me, but I am a bit confused here. Are you looking for Street Bass (the one you really feel and hear) or Competition Bass? The specs I gave were for Competition Bass. If you are planning on playing music through it, I must admit it will lose a lot of quality and sound (as my friend would say) craptastic. It's meant to hit hard, not sound great. I can re-run the numbers for a better sounding curve, but it may not hit as hard.

For the 15", I am assuming you meant the 1250.1 amp...   6cf with a square port 3.5"x16.25". I haven't run these numbers through WINisd.

Any particular idea you had?

Ganbatte ne