Emorrisiv, I've heard the Acoustats sound great with a set of M-60s and a set of ZEROs. The guy that had them also had an ARC Classic 60, and he had to use the ZEROs with that amp also. They seemed to otherwise present a challenging load for a tube amp, but my guess is that they were doing what a lot of ESL manufacturers do, which is to set the impedance low to try to get transistors to work with them.
At any rate Acoustats and tubes are a great combo if you can overcome the impedance issue, and ZEROs do that quite well.
At any rate Acoustats and tubes are a great combo if you can overcome the impedance issue, and ZEROs do that quite well.