Here's what my single KF92 can do in my room (4.5m x 4.7m, with doorways open to hall and kitchen). Measured at listening position. Traces are labelled as LFE dBFS at reference volume so "-40" should be 75dB SPL (actually higher in the bass region due to downward slope).
Sweeps at various levels, to give some idea of what the DSP limiting does. Measurements with UMIK-1 - not sure how much to trust it at such high levels. (I understand there's an internal gain adjustment that might help, but didn't try it).
The way that 20Hz gets "pinched" most at high levels, seems a bit weird. I wonder if with the sweep going upwards, it takes a bit of time to respond to the high level and kick in limiting, and so 20Hz in the sweep gets lowered more than 10Hz?
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