A harsh midrange can be one of the worst traits a speaker can possess and that's why buying without audition is a total crapshoot. While audition is not always possible, it is, IMO, impossible to "research" a speaker through reviews or online posts because the reviewers have different rooms, different electronics and different tastes. While I agree that some break in is necessary, I would say give them 2 weeks and then return them if you can. Or you can rebuild your system around the new speakers, i.e., new cables, electronics, etc to get them sounding better. Or, you could find recordings where the Dynaudios shine and only play them. Don't think for a minute that some audiophiles don't take this approach, either consciously or subconsciously. Mark Levinson many years ago talked about the concept of the system dictating the types of music we play. But all in all, if your B&Ws really work in your room, why not keep them and upgrade other parts of the system? Changing speaker cables might make a huge difference - or none at all. That's why it's best to buy with audition. but I know it's not always possible. Good luck. BTW - when I audition a speaker, I will always play something off the Brubeck "Take Five" record. Paul Desmond's alto sax will expose a harsh midrange immediately. It also happens to be good music, but that's a bonus.
Okay, How Important Is Speaker Break In? (Dynaudio Contour 60i)
I have been running 25+ year old B&W Matrix 803 S2 speakers in my 2-channel system for about 15 years, and I finally treated myself to new speakers. Mock me for buying based on research alone, but I got a really good deal and just unpacked my beautiful Dynaudio Contour 60i's. The Dyn's are not broken in, just starting to play around with different songs, but I am expecting an improvement out of the box, and not getting it. They are no more revealing, and slightly harder and more jangley in the mids and highs. The bass is of course much better with the big Dyns, but the B&Ws with the Dyn Sub6 subwoofer I was running were better. I have very good equipment so it is not a matter of driving bigger speakers (ARC Ref preamp and Bryston 7bSST2 monoblocks). Unless speakers get A LOT better with break in, I thinking these Dyns may be converted back into cash. Thoughts? Thanks.