Okay, How Important Is Speaker Break In? (Dynaudio Contour 60i)

@mathiasmingus  I tried a respectable tube amp on the speakers and though it sounded very sweet, it just didn't deliver the "slam" that I want.  Of course, amps are all very different from one another so I can't speak for what an ARC amp would do or any number of other great tube amps.  The Contour 60i do demand some current to make them come alive and deliver what they are capable of.  I settled on a SS amp that has a softer sonic signature than most.  I bought a Balanced Audio Technology (BAT) VK-255SE.  I also use the very well paired BAT VK-33SE preamp (lovely tube preamp).  It's a wonderful matchup for the Contour 60i.
So the bottom line is, if you are finding the Contour 60i speakers are delivering what you had wanted then at some point make a change in your electronics that will better suit them.  You have the preamp, just get the right amp to address the sonic signature that you desire.  And yes, a very good power cable and signal cables are very important in delivering what any electronics have to offer.
Enjoy the fun ride!

It’s always entertaining to read this type of discussion here. So many adamant opinions. Many of which are completely subjective.

Speaker break in is real, as you’ve discovered.

So nobody has even asked if you ever had the B&W’s serviced. The capacitors in the crossovers of any speaker that age are most likely not close to spec and have skewed which driver is delivering which frequencies. Since this can happen slowly your ears may adjust and you never recognize it.
  
But hey, with nearly 30 years of experience as an audio engineer what would I know.

I’m breaking in new PMC monitors now. The company states 50 hours minimum, but that’s because they partially break them in before shipping. The change in the first 20 hours I’ve had them has been significant.

some speakers really demand strong solid state amps to sound their best, tube amps cannot handle them

other speakers thrive on tube amps, presenting more friendly loads and efficiency, but to be as efficient and amp friendly, they sacrifice some performance parameters (while excelling at others)

when one starts out in this hobby it is most important to find the right speaker for your room, your listening, your music - then treat the speaker as the given -- and mate the amp to handle the speaker and deliver the best possible sound from said speaker

as you move along in this hobby and hear what different speakers and amps (as combinations) can do, you start to become more open to changing to different speakers that can in turn be driven by sweeter, more palpable sounding amps (be they tube amps, or lower wattage simpler ss amps)  to deliver a nature of sound you like better

it is an experiential, iterative process

I just bought a pair of dyns and they were awful and lifeless out of the box. Played them two days straight in a closed room. Entered the room after the two days and shocked at the difference in sound. The dyns became much more open but a bit harsh. Played them a 3rd day for 8hrs and their was not a hint of harness. 

For glissando, no the B&Ws have not been serviced - thanks for the call out.  I had no issue with the B&Ws, just wanted the indulgence of newer, better speakers.  If I keep them, I may get them checked out.  
For jjss49, thanks.  Based on my somewhat limited understanding of electronics, the Dyns are power hogs, so big SS amps are desired and what I have.  Now, I have read some so-so reviews of this model (7bSST2), so that will be on my mind...though the system sounds pretty good now.  To your point, I have a sense that with age I will move to quieter, more refined components, but for now, we are going with big and brash!
For dwest, yeah brother, harsh was the word, but world of change now, and I still have a lot of breaking in to do.  I am a Dyn convert.  Enjoy yours!