Try a target time of 185 msec, or rerun the analysis.

500msec seems like a very long target RT60, and I'm finding best results around 185msec in my 21' (6.4m) x12' (3.7m) x7' (2.1m) space.

Is it possible that you are used to boomy / overly reverberant bass? I haven't found a need to alter levels with MRC engaged.

Cheers,

Surround Music Fan/Computer Geek/Curmudgeon in training.
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