Hi Salvador,
Thanks for the interest, man. First off, call me at 317 299 5578, so that we can talk in detail.
Second, as for your setup, that's exactly why we started on the Etesian. Make a good sounding pre for VERY little money specifically to fix the pre catch 22 in receivers. The amp goes between the receiver and the axternal amp, and with the HT bypass you can run the etesian as your main pre amp for 2 channel music.
I'm very happy with the final result, even though as a passive you're obviously quite a bit away from the Tempest. Realistically, looking at your system, the Etesian / Stratos combo will completely reform the Denon based system, as it should for the extra $$$. Also, most importantly, the synergy of the Stratos with the Ref 20's is excellent. So, it's all good here.
As for MAxcast's advice, I'd might look into that as well. Ultimately, it all depends on the $ and application and most use. The first definitive step here would be going with an external amp first.
Call me,
Klaus