That's good to know. Do you have much experience with their high pass filter? I do mostly stage-lip recordings, sometimes with mics only 1ft from the floor (on stage)picking up footfalls or am fighting HVAC roar.
Just wondering (in general, possibly) if it's really better to cut out what I can at the source or wait until post. In other words the lo freq noise isn't loud enough to cause overload or whatever, just annoyance. And I realize all filters, be they mechanical, electrical or software, are imperfect in various ways.