I don't know what you meant by "manually inputting the filters into MuleEQ". In my experience, using the App and Ratbuddyssey, you can get a very flat FR in the lower frequencies, then it is a matter of putting a tilt towards 20 Hz if you prefer the so called Haman curve.
This is what I get with Audyssey that I could not do with minidsp+REW on top or without Audyssey. So to me Audyssey with the App/Rat is a much better way to do it, without all those extra wires.
The first graph took me some time, but when I moved the couch recently I re-run Audyssey. This time I just edit it with the App/Rat and added only a few data points so it took about an hour. The result is in the second graph.
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