I have a pair of vintage JBL L100Ts mains and found a pair of JBL L20Ts off of eBay to use as centers. The bookshelf sized 20s were two way speakers using the same midrange and tweeters as the 100s. I tried using just one, and both as center speakers, and could not hear any degradation in sound using both. Since my TV is a big Mit 70" rear screen, the two speakers placed side by side horizonally look better anyway. If Dahlquist made bookshelfs using the same tweeter, and midrange, you be able to get a good match going that way.