A follow up here. I found no dealer in Oslo with a big tube amp, willing to let me try it. Also, dragging 80 kgs is a big burden. Better, then, to listen to others who have tried this, before investing a lot of time and a poor back (prolapsis in 96).
Jaybo, above wrote to the essence that my Krell is already a state of the art case. I think he is right. I find that many things that I thought were due to the "analytical" solid-state perversions of the Krell are in fact other things, that the Krell just communicates. I thought it was "transistor" sound, but changing my system on other parameters make it go away, like using cerapucks under the amp and speakers and ceraballs under the turntable record player. And even, sandbags on speakers and sub.
The Krell is at its best when it plays loud, 90-95 decibels, measured from my listening position (ca 3,5 meters from speakers). This is a bit load for my taste, but at that point, the amp runs at mainly class A, and there is not much to critizise. Especially the synergy with the Io preamp is good. Since the Io is heavily tube-loaded, it tends to correct the trans errors in the krell.
oystein
Oystein