[Ethan Winer]

Bob,

Calling this comb filtering is somewhat of a misnomer. It is really about
multisource/multipath interference.

I do understand your distinction. But it seems to me it's still comb
filtering, just more than one set of interference responses.

I also agree with your basic premise. As I see it, the parent property of
all of this stuff is boundary interference. Room modes and comb filtering
are SUBSETS of boundary interference. You can have boundary interference off
a single wall outdoors, and you can have comb filtering when sound waves are
traveling in the same OR in opposing directions.

--Ethan