WF, if I followed your experiments, even the M60 developed those upper bass/lower mid peaks when you connected the center channel output to it. I'll take some wild swings at it. Don't know the DB940 details, but I remember that many of those Sonys had graphic equalization provisions. If the DB940 is one of them, is the equalizer set to boost those frequencies? Or, if it's there, set it to reduce those peaks? If not, I don't have any idea why either Avia or the 940 would have a problem in that center channel frequency range.
