Driving 1 ohm

I wasn't recommending anything just defining a high current amp.
The Zero Impedance device looks like an autoformer or a similar device. It doesn't seem like something an OTL amplifier design would promote.

Best amp to drive ESL?
Roger Sanders (http://www.enjoythemusic.com/magazine/manufacture/0702/index.html) of course suggest to use solid state amplifiers, specifically his own design.

I believe that Andr did not strated the tread asking advise to help him to find different amp then one he uses and enjoys - rather what harm it can endur by driving 1 Ohm load.

...of course when I owned Quad ESL 63 I used only tube amps (heh, heh, heh...)

Regards
Simon

Simontju is right on that one. The 2500A inherited the Acoustats. Long story short : I had Acoustat model 3 for a year and decided to have them rebuilt in 2+2 s. What I got back is something supposedly easier to drive but tremendously upgraded on the full range. And that brought me the concern. The rest of the electronics is probably forever : Simaudio Eclipse, CJ Premier 16,cables. The 2500A is here to stay until I get upgraditis again but for the time beeing, the WAF has been tested enough with the 2+2 s in the living room. I would not dare testing it again with large monoblocks,class A or tube amplifiers, at least for awhile. Class D maybe a solution but did not have the chance to audition some. In my vicinity(Canada), they remain quite scarce.

My Acoustat 2+2's do amazingly well driven by a PS Audio HCA-2 amp. Grab one here on Agon for $600 used.. you won't be sorry, and your back will thank you!

If they were Apogees or Kappa9's, a rugged SS amp would be the way to go but for ESL's, Ralph is right.

Another option is "monostrapping" or parallelling an identical pair of stereo amps. That would double the current and wattage and halve the output impedance. Some manufacturers don't approve of this method.