@pennfootball71 I don't hear any sense of these being slow thus far. I suspect Rel subs very difficult to make generalizations about since main speakers and amps have relatively large influence on how subs perform. So far, with my Klipschorns, the T9x has virtually no impact on bass performance per se, don't really reach lower, just a bit of db boost in freq. where in room response at my listening position begins to roll off. These all about sound stage expansion for me.
Going into Rel purchase, speed was of utmost concern for me, assumed these might be slow. Using this reasoning I partnered with Ac receptacle and power cords that I know supply fast, tight bass, considering silver high level speakon wire if I hear some slowing in future.
If these are slow, my past subs and present Genesis sub would be slower than slow, even with dsp slower than high level circuit in these Rels. I'm also open to the fact that over time I may hear some sense of slowness, why I may wish to upgrade to Reference models at some point.