just off hand, do you think I can get the same output...here are the specs

Lighting Audio 10" sub. 300wrms .75 cubes sealed

Image Dynamics 10" sub. 250wrms. 1 cube ported

My car's resonant freq is 47hz so I might have the box tuned to 47hz. Not looking to be louder but hopefully have the same SPL output.

 

I'm sure the ID setup will blow the LA away.... and probably sound a lot better doing it. Even with the ported box. But since you are tuning so high.... i don't think your going for SQ, huh? Also, if your car's resonant frequency is truely 47Hz, you'll want to tune a hair under that. SPL will peak just over the tuned freq. Tune to 43-44Hz.

 

I might get the box tuned a little high to get a spl/sq setup

 

mid 30's?

 

Exactly, be warry Paul when tuning that high. You're gonna get a nasty peak that can destroy SPL or require too much EQ'ing to fix.

 

I was speaking w/ one of my friends and we might end up using a tunable port. Basically we can adjust the port size for two different tuning. So the setup is going to be tuned for around 45hz for spl competition and have the box tuned to around 30hz for everyday driving. Though from the suggestions I've been hearing, I might be better off staying with the sealed box rather than having a new box built.

 

I generally like sealed for SQ applications, but proted can have good SQ as well if done correctly. I do like your presto-chango-port idea. If I was having to pay someone to build me another box that would probably deter me as well. You're looking at around 2-5 db difference though, just depends on the sub itself. And yes, tune a few ticks below your frequency.