Integrated tube amp for quad ESL63

Do you have a budget? Because a NuVista 800 would be awesome.

Anything would sound great with those ESL's. What about darTZeel?

A pair of Dynaco Mk III's with a passive pot connected to your favorite digital source! That would be a tasty combination indeed!

What about Air Tight ATM1 ? Heard it was a great configuration. 

good to be aware of this

excerpt

"Unlike the original Quad Electrostatic, which had a tendency to break down if overloaded for an instant, the '63 has a sophisticated protection device designed to short out the input signal if its level approaches an amplitude that could do speaker damage. Shutdown is claimed to occur rapidly enough to provide full protection to the speaker, but some power amplifiers will not tolerate output shorting and may blow fuses or sustain serious damage. Tubed amplifiers won't be harmed by this, but some solid-state amplifiers could be. If in doubt about your amplifier, check with its manufacturer or, to be safer still, use the speakers with Quad's own amplifier."

https://www.stereophile.com/floorloudspeakers/416/index.html