My plan for some bass...

2fast4thelaw

If you want super low bass than I suggest a ported enclosure tuned to 20 to 25 hz. Your Infinity Perfect sub is a good sub and I personaly would roll with it and port that badboy.

You wont need a 1000 watt amplifier! The Amplifier you have now will work fine for now, but I highly recommend finding a Phoenix Gold Bass Cube. This little unit will protect your sub from subsonic frequencies and allow you to eq your sub and boost its sweet spot. This unit is worth its weight in gold, no pun intended. I will warn you! You need to learn how this unit works and DONT over power your sub otherwise you will be left with a blown sub. This is coming from experience as I have had to have a few JL subs rebuilt from getting to over zealous.

The combination of a ported box tuned low, Bass Cube, a good 12" sub, and 250 watts rms will deliver absolutely mind blowing sub bass!

A sealed 15 inch sub will not even come close even at twice the power.

Ported boxes are very efficient and can play much lower than a sealed box if they are tuned for it. A big misconception is that ported boxes are boomy and not accurate. This is not true if you build your box correctly. Some of the very best sub bass I have ever experienced is from a ported enclosure. A properly built ported box will sound very smooth and transparent and you will feel lows that you never thought were possible from a 12" sub.

If you provide me the Thiel Small Parameters of your sub I will model you the correct size of box and correct size and diameter of the port and each one of your goals you listed will be met!

As far as ohms, I don't recommend going below 2 ohms or your asking for trouble down the road. A dual 4 ohm sub wired in parallel @ 2 ohms would be optimal for your current amplifier. Any lower than that and you will be buying a new amplifier within 2 months.

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