Hi, I am the former unhappy user with 1.3SE and 8200P MkII.
I have been looking for the reasons of that lack of bass, and I have found them out of the amp.
First I thought that the guilty was the amp, as it sounded like it had no current to move the speakers. Finally I took it to a dealer and tested all my gear separately with several different components.
About the amp, I paired it with Dynaudio Contour 3.0, Gryphon pre and Wadia 861, and I can say that it was able to move the speakers and get fine sound. I liked it best without the preamp, the Wadia direct into the amp.
In fact, now I find the 8200P as what it is and people rave about: a fine and powerful amp with very good controlled bass and sweet mids and highs, highly recommended with ultra-revealing Dynaudio speakers.
Now I am thinking about a SA102, not because the 8200 isn´t enough for me, just for the upgrade worm. If I had the money, I would give a SA102 a chance with Special 25´s.
I must say that all people at Plinius, specially Peter Thompson in New Zealand and Vince Galbo as USA distributor, though I am spanish, have made a very good treatment for me, I asked them and every moment they have been worrying and helping with my problem. Chapeau!
As soon as I get my problem solved, and I think I have found it, I will write an explaining post, and I repeat the amp works fine.