To answer ur question, NO! The center channel does not have to match. But, I highly recommend it.Your C1s have the ESOTAR SQUARE tweeter...not the esotec. In the Dynaudio line, u have two options: Contour SCX center, or the Confidence center. They both have the ESOTAR SQUARE tweeter. The Contour will be about half the price. And there are deals to be had right here on Audiogon. I find that matching the center for HT has a certain degree continuity in sound quality. Same tonality if u will.I have the C2s and a Contour SCX center. This combination works fine. However, I wish that I would have waited a little bit longer to get the Confidence center. I'm still considering the upgrade. I guess that it all depends on how well u want ur HT presentation to sound. I've heard other systems that mixed mains with different brand centers. To me, it's noticeable! And that is distraction for me. Others are not as discerning. I've always felt that the equipment facilitates the goal of the director..."to suspend your disbelief" while watching a film. I really enjoy watching film...and to listen to a soundtrack that gives u goosebumps while watching, can be very rewarding. But, then again, this is coming from a guy who has enjoyed film all of his life. I hate using the word "serious," but I guess it all depends on how serious u are about viewing movies.