@kqvkq with regard to Quad ESL 57s the recomended maximum amp size was 45 wpc as I had them and when Quad brought out their 405 current dumping amplifier they stipulated that you had to put current limiting resistors in it to limit the amp to 45wpc when using the 57s. I'm afraid I know this to my cost as twice I had to replace bass panels as I thought I would be smart and not use the resistors.
high-efficiency loudspeakers
What is the best high-efficiancy loudspeakers? If you have it, are you happy ?