CEA Standard (THD <10%, 2 Meters) SPL @ 20/32/40/50/60 Hz:<o

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JL Audio F112:.... 92.8/112.4/116.2/113.3/117.6
SVS PB13 Ultra: 110.6/113.5/115.5/117.5/117.8
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So the F212 would output even more than the F112, and dual F212 even more.
I would not change a thing if I were you. Just keep the F212 and be happy.