Hey...I am amazed that any tube amp can do them justice, because of the enormous power needed to drive the deadly combination of 3-4 ohm/83db efficiency issue.
I thought this too until I plugged my Manis into my Tad 60 tube amp. In addition, I had it switched to Triode mode (27 w/c). While it won't blow the doors down with Rock music, it sounds amazing and wonderful with any music that has a lot of mids-highs.
As far as loading your room - try a subwoofer with your Manis. I use a Rel Storm III with mine. Crossover is set at 30hz and it integrates beautifully. You don't know the sub is in the room, but the room is fully "loaded".
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