I'm not an expert on the subject, I do just question why adding an extra 7 feet induces an improved FR ?
I've got a vague understanding of why but the rest goes way over my head.
If your subs have a variable phase control like my SVS you might try using the correct distance with different phase settings?
As you said "hypothetically" the incorrect distance setting shouldn't be the proper thing to do.
There may be others here more educated on the subject that can address this here.
Or you might reach out to Mitch
@mitchco of Accurate Sound for more in-depth answers.
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