Tube amp for "difficult" speakers,,,

Tvad I don't have the specific info at hand but my speakers are a good match to my VAC 70/70. Just for others,I found this article on the VAC website.

http://www.vac-amps.com/Technical_Monograph_90-9.htm

Sound Lab (and all true electrostatic speakers) are a difficult load for the previously mentioned reasons. However, there are tube amps that are very capable of driving them extremely well, Wolcott, Atmosphere and CAT being good examples.

Thanks to all for interesting suggestions and advice.

Rlawry - I have never seen measurements of the Consequence, but the specifications say "Impedance (nominal) 4 ohms, Impedance (20-200hz) 3.6 - 6.7 ohm, Impedance (200-20khz) 2.8 - 4.7 ohm". I am not sure what this means in terms of difficulty or irregular dips. What is clear, is that these speakers thrive with power - the more, the better. (Dynaudio created an inhouse amp, the Arbiter, for developing their speakers, which delivers something like 800 watts and had even more hefty power (I think) than the Krell). Actually, Michael Fremer wrote back "try 2 Krells" and although I didn't quite catch on at first, I do understand what he means (the Musical Fidelity website has info on headroom / power).

Jaybo - the speakers do sound good with the Krell FPB600 in many ways, best with the amp running on higher bias levels, as noticed by Colloms in the Stereophile 97 review already. I measure around 89-94 db 1 meter from the front of the speaker, then they have great dynamics, depth, and an effortless quality to the soundscape where many things can happen at the same time without any congestion. This is where a good s-state/5-way speaker system leaves others in the dust, with complex music especially. So when you have a rock group with orchestra, like Procol Harum "In Concert With The Edmonton Symphony Orchestra", you really get it all.

Not so good for my neighbours though, and a bit more volume than I need late at night. And - there is something with tubes, triode in particular.

Tvad - Pass labs XA-5 noted, will try to find a chance to listen. Likewise, Pubul57 - Music Reference RM9. Wavetrader - thanks, will try Kevin Hayes at VAC, although I note Tvad's point that 160 Vac watts was not enough for his Dynaudio-driven Silverlines. Not so surprising.

Semi - so did your older gentleman who used to own Consequence, give up in the end? That a medium powered tube amp from Canada sounded good is interesting, but I have considered things like Sonic Frontiers Power 3, thinking "not enough".

Changing the speakers is of course a possibility too. I am not dead set on the Consequence. Over the years I've grown to like the Dynaudio sound (e g the Esotar better than most other tweeters). I have read that the Dynaudio Evidence Temptation can sound good with tubes, they are a much easier load, but they are out of my price range. Have anyone compared them to the Consequence? Trouble is, the speakers that I've thought were clearly better, tend to have astronomical price tags, like the amazing Verity Lohengrin (heard at a hifi fair in Horten here in Norway - and even then, I was not sure, on all parameters).

My conclusion, so far, is to keep looking, and try a big tube amp when I get the chance. If nothing works, perhaps the speakers will have to go. I will of course report back to this forum when I have found a good combination.

Rlawry - I mailed Dynaudio, and got the answer that they don't believe in tubes for the Consequence, they mainly adviced me to try the Temptation. Yet their letter did not convince me that they had done much research regarding newer big tube amp designs for the Consequence.

One more point, for other people with good / 'difficult' speakers needing big s-state amps. If you want to chase out transistor sound, look at the system as a whole. I have found that there is a lot to be done to improve the sound, like a dedicated line, good stand, room damping, and a good tube preamp. In my case, upgrading to the all-tube Aesthetix Io was a huge improvement. I've also made a lot of tweaks, mainly to improve damping, including a Bright star sand box and inner bike tire under the record player. In fact I may even have overdamped some things. Somewhat surprisingly, a good sub (Velodyne DD18) has also contributed.