Just to follow up, here's the graph from swapping the center and right speakers in my setup:
A reminder: this was a quick-'n'-dirty test taken in SoundTrack Pro with the built-in mic from my MacBook Pro, which in no way has what you could call a flat frequency response, but the relative difference between the TSBLs and the TC2 should still be obvious.
When I swapped speakers, the Audyssey-set channel levels and EQ also reflected this. The original readings were:
When I swapped them, it changed to:
The spike in the EQ around 8 KHz also moved with the TC2 from C to R. Very similar results came from a swap of the TC2 to the L channel; so I expect it's nothing to do with the receiver. Let me know if you guys think of anything else I can try -- I have until Monday before the TC2 gets picked up by FedEx Ground (see below).
I spoke with Dennis Suler at tSc this morning, and we're trying to figure out what the issue may be, so this TC2 will be going back as well. In the meantime, he's sending me another TSBL to act as a center channel to see if I'm happy with that. If so, then he'll refund the difference between that and the TC2. I made it a point to say that I'd like to hear back from them on the disposition of the TC2, if it turned out that somehow I beat the odds and just happened to have two defective ones in a row, or what the deal exactly was.
Hopefully we can figure this out, and I can get a TC2 that works as expected. If not, perhaps a third TSBL is the best answer. Is this in any way endemic to center channel monitors that have dual-midrange drivers? Is it just overpowering the tweeter, making it seem that I'm not hearing what I'm supposed to hear? (This is my first experience with this type of speaker.)
It seems the folks at tSc are definitely trying to provide good customer service, even if the return/call tag/pickup process has a maddening degree of ambiguity; but I suspect that has more to do with their choice of using FedEx Ground as their shipper, than it does with tSc themselves.
I'll report back once I hear more details from tSc.