Moderator wrote: If the tweeter wasn't working you would certainly know it. My guess is the microphone was too far off axis to the tweeter. Is the center speaker's tweeter at the same height as your left/right speakers' tweeters?

No, you can't swap tweeters. Take the speaker to your dealer if you are concerned it is defective.

No, center channel tweeter is above the L/R tweeter height. All 3 speakers are on swivel mounts aimed at the main listening position 12 ft away. What are the dispersion characteristics of the 50C? Here’s a pic.

I imagine if you move the mic higher or further away the discrepancy will disappear. How does it sound? If it sounds good, it is good. I wouldn't put too much stock into what Anthem says about the graph, they apparently have no idea what the response would look like if the tweeter was not working.