What would be an ideal box for the 12L5, would 2.7 ft/3 at 35 hz be good, it will be powered by an mtx tc6001 amp and the sub is a dual 4 ( so wired at 2 ohms)

 

2.7cf^3 @ 35hz and an MTX amp is good start. What year is the sub? Where are you getting the box?

 

use the re audio enclosure calculator. after all displacements, make the enclosure around 2.3-2.4 cubic feet @ 35hz. port width should be no less than 2". play with the dimensions and see what you get.

 

its an 07 sub and i did use the re calculator so 2.3-2.4 after port would be ideal instead of 2.7

 

That calculator is inaccurate (because of port end corrections), use the 12 volt's (which doesn't correct for the end of the port, do it yourself). Find the dimensions you can use for a sealed box, and then minus port area from it for actual space. I would do 2.5 cubes.

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