first time building a ported box.

I spent the last week tuning and listening to this box. It started with one 3.5" wide port that was 4.5" long. No output at all, so i did two 3.5's at 15.25 each for 30 hz, that was louder and lot more flex but only three songs i have hit right on that, so i did three 3.5" at 15.25 for 38 hz. the box is 3 cubes, it was a sealed box for two 15''s. Now i just need more power. Ill make a vid of what it does on 600 rms and two twelves.I hope 38 hz suits my needs..