And looking at PD series:
https://www.youtube.com/watch?v=zindDSFQ65s
https://www.youtube.com/watch?v=dQp6gCpgc7s
They use horn based tweeters and pro-audio style drivers. They have their own sound. I think they were going for a Klipsch horn-based type of style, but they didn't quite make it. They sound okay, but definitely don't have the warmth, clarity and liveliness of the Klipsch (such as Forte III).