Using tube amp with electrostatic speakers.

Very few amps can drive the CLS (esp. of that time), which is why they -IIz came out pretty quickly.  ML's with dynamic bass are not that difficult to drive with some tube or hybrid amps - which is the topic.

Off topic - I've never heard any tube amp that could drive some tough full range panels such as Scintilla's, or the CLS.  The CLS IIz can be driven, but not by any reasonable priced tube, and I've never heard a tube amp that doesn't make drums sound like a rotten tomatos getting hit with a mallet when trying.  I owned mine for 15 years, and with 3 dealer/friends vying for my business I heard just about all of them.

No matter what amps I try, I always end with back with my Nelson Pass products - which besides the Aleph Series can drive any panel or hybrid and avoid the SS hardness tube heads so dislike.

I'm not here to denigrate or deny anyone else's tastes or findings.

Firstly, I never owned any versons before the IIz, and only heard a friends I many times as he sought to find an amp to drive them - Jadis, ARC, Krell, yada yada - he sold them.  The Scintilla's are the only speaker that was harder to drive and that's my experience in my 45 years in the hobby. 

There are tube amps that can handle CLS IIz's but they are either very expensive, or they are hybrids (as of about 2004).  I have never heard any tube amp under $15k that does justice to the bass - IMO.  Now it's been a long time since I've had them, and the state of the art has obviously moved ahead, so quite possible, but not in my time.

After I sold the CLS's, I had brief flings with the SL-3, Maggie 3.x, Quad 998?, and lots in between.  Retubing costs for amps, sourcing fancy types, and prior unsatisfactory results/cost has pretty much cut me off from tubed amps as a viable choice these days.  A preamp? - perhaps but I have a Pass L - which trounced my ARC SP-15; - I mean it was sad (do miss the polarity switch however) Headphone amp - perhaps, but I liked the Ragnarok more than the warmer albeit colored tube options at similar prices.  Coloration levels a magnitude better, and bass?  much better.  Oh yeah, a nice integrated amp too boot.

My favorite speaker of this century is the Verity Parsifal decidedly not a panel and driveable by tubes.  Still like the Pass X amps better than anything else on them, but, nothing really sounds bad on them - the spiritual grandchild of the ProAc EBS.

We aren't quite in agreement, but in this hobby with so many people dying to disagree, I prefer to agree, or to find other people's ideas interesting and hopefully charming. 

Keep writing.