Aloha,
Over time, we have run into comb filtering being offered again and again as the root 'confuser' of subjective listening reports.
Proponents of comb filtering cite the large differences in frequency emphasis or de-emphasis that can be seen over very small spatial positioning intervals. These differences are mentioned as the solution to almost all subjectively reported audible differences audiophiles hear between pieces of electronic gear, but I think this is not a fully appropriate answer.
If comb filtering were such a bugaboo, wouldn't you expect the sonic differences between pieces of kit to be minimized rather than emphasized?
Bear with me...
Proponents of comb filtering as