Hello Eagles, while I do know that others can sometimes feel very, very strongly about "matching", I think it can be a bit over-exaggerated for HT. Just one opinion here.
Currently, my present HT setup is a 7.1 PSB system, but the center channel is a Martin Logan with an ATF tweeter + mid (x-over'd at 500hz). Trust me, I did entertain the idea of trading my ML in for a matching center. My dealer would accomodate me, no problem.
The greatest advantage I would get with a large PSB center would be the increased dynamic range, extension, etc, stuff that simply comes from a larger speaker (they get really big!). The ML has very poor extension.
But I find that the ATF is soooo good with dialogue, IMO. I rather have dialogue as discernable as possible, with as little sibilance as possible (and this speaker has the lowest amount of sibilance compared to any "center channel" that I've heard). To give up this excellent trait just to have it matching doesn't work for my desires. However, I did not audition nearly as many center channels as I did stereo mains.
I've been watching a lot of movies lately. The most common front pans I find are cars passing by. I would be loathe to give up vocal excellence to make passing cars sound a tiny bit more consistent, and not that I would notice because I am listening to the actors' voices over that background "noise". For music, I think matching is much more important, but I don't listen to multi-ch anyways. For HT, most panning sound effects are unfamiliar to us (unlike with musical intruments and the human voice), such as alien spaceships (pick movie), tank shells (well, unfamiliar to me anyways, the Pianist, Behind Enemy Lines), flying fairies (Pan's Labyrinth), etc. OK, I appreciate the idea of making these "artificial" sounds to be more consistent, but since they happen to be unfamiliar to me, I might be much more forgiving.
With either ML or PSB, I think that I do, or would, suffer off-axis issues (unless I got an upright bookshelf). (The ML has a top mounted tweeter, but the off-axis issue is due more to the speaker tech, AFAIK), If I did this all over again, or wanted to upgrade my center (a veritable future possibility), I would definitely audition center channels that best deal with lobing. Perhaps B&W, Revel, or a coaxial KEF for instance. Still, a bookshelf is better designed.
I have no idea if ID brands would let you buy a single bookshelf, but I don't see why not.
In conclusion, my opinion is that one should pick a center with these attributes, in order of importance according to ME:
- clear dialogue with zero sibilance if possible
- off-axis response, or the avoidance of lobing as much as possible
- extension and/or ability to crank, dig, etc, as HT asks the center of sooo much
- matching.
I know some people think Im crazy, but hey that's ok!