I have played a bit around with the 2245H in Winisd and some solutions are a bit intriguing.

8 cuft tuned to 26hz with 6db boost at 26hz (Q=2) + 160hz 18db/oct low pass filter gives this curve:
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But needs a 20hz 18db/oct high pass filter and still reach xmax at roughly 230W
This is the B460 tuning and boost, but with a higher Low pass x over.


Alternative 2 looks like this
10 cuft tuned to 23hz with 2,5db attenuation at 90hz (Q=0,7) + 160hz 18db/oct low pass filter
No High pass filter are needed, Xmax are not reached until 380W
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and it has a roll off that I believe would match room gain quite nicely. the draw back are that sensivity above 50hz are only 92db/1W But how much of the B460`s rated 94db/1W sensivity are real with that in mind that it needs 6db of boost at 26hz too be relatively flat?