Zu have always self powered their in built subs in their top models
But maybe there is some work to do in getting current iteration to work
Additionally, Zu likely to go for a totally different solution than the front firing 18"
Remember, this was prototype #5 of 11, and Sean investigating #s 12 and 13 ahead of the final production pair to be released officially at Munich
Nothing to do with Zus, but this shows how different decision making styles are. If I like something, I first try to break it. Listen to it in different systems and rooms, or feed it something different. Apart from getting past the first 5 mins, it helps tide over the initial euphoria and impact. Allows time to wean myself off that component