As a former owner of the 804's (I now own the 803's) I can tell you that the right electronics make a big difference. I ran mine with a Classe CA300 and it was a pretty fantastic combo. I also tried it with my HT set up; a Harmon Kardon 500, only 85w, and it was somewhat as you described. I can't speak to your electronics as I am not familiar with them. I wouldn't rule out the room qualities either. The size and shape can drastically alter the quality of a good speaker.
good luck, I think you have a fine speaker.
good luck, I think you have a fine speaker.