Not sure about your def tech speakers but I am using the Bel Canto pre3 along with Bel Canto S500. Last summer I traded a pair of speakers for a Jolida tube amp, don't recall model, and put it in the system. The Jolida did not work to my liking at all. I mention your speakers because my Meadowlark Kestrels have a very ear friendly presentation. Where the Bel Canto equipment compliments the Kestrels, the tubes may have added unneeded warmth.
Speaking of warmth, I tried this experiment in August. My normal routine was to turn the amp on and leave the room for 30 minutes while the amp warmed up. When I entered the room I was struck by a 10 degrees rise in room temperature. Not for me thanks.
Speaking of warmth, I tried this experiment in August. My normal routine was to turn the amp on and leave the room for 30 minutes while the amp warmed up. When I entered the room I was struck by a 10 degrees rise in room temperature. Not for me thanks.