Tube amp for "difficult" speakers,,,

Tvads assessment of the issues is a sound one.

Atmasphere takes a very different approach to tube amp design that just might fit the bill. I would investigate this further if I were you.

This is a topic of interest for me as well in that I like what I've heard recently with good modern day tube amps but my Ohm 5's (and Dynaudios) both present a challenging load that I do not believe most tube amps would handle very well.

O Holter, I'd be very interested in hearing about your results if you go the tube route with the Dyns.

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

Jaybo is without doubt a "voice of reason" when it comes to giving good equipment its due rather than mining for perceived shortcomings.

I had some experience with the Dynaudio Consequence’s, many years ago, and I still consider selling them cheap one of my biggest audio mistakes. But at that time I did not have a dedicated listening room and as they need a large distance between the speakers and the listener, the best listening position was at the place occupied by a large dinning table…

I heard some of the best sounds in my life with the Consequence’s and the Primare 200 system I am now advertising at Audiogon in a 80 square meter room, but the Krell amplifiers (KSA300s and KAS at that time) and Cello's were the best with these speakers. The Dynaudio Arbiter's and the FM Acoustics were only dreams for me, but a reliable friend who heard them with the Consequence's is still recovering after 15 years.

From my many experiences, including Audio Research Classic 150s, I would not advise using them with tubes, independently of power or electric compatibility. I have now a speaker with a similar behavior in my system – the wonderful Krell LAT1000s. They are a great speaker with the Dartzeel amplifier (200W, current limited) but my VTL 750s even in pentode mode can not control them.

I would advise you on upgrading your FBP600 to 700cx – they are completely different amplifiers, the 700cx is much faster and it should complement the Consequences much better. Also something tells me that the conrad johnson premier 350 – a great LAT1000 driver would be a good match, but is also only a guess.

The big Wolcott amps are reputed to be able to fill your needs.