Update:
I have an Allnic T1500 MKii on loan: 300B SET design for Korea. The 10W output from the EH 300Bs are providing decent volume in my room. The unit is new out of the box, so I am still breaking it in.
Currently, my reference for volume has the attenuator at 12 o'clock.
This is a special amp...
http://allnicaudio.com/product/t-1500-mk2/