If there was ever a contentious topic of discussion not directly involved with the Quad electrostatic speaker itself, then this is it. I think I have seen and read more correspondence on the matter of amplifiers than everything but the coating material on the diaphragms and the "Did they coat one side or two?" question (See FAQs, by the way, if you would like to know the answers to those questions).
I have started this page in response to a lot of inquiries to do so, and have commenced with material sent to me by Christian Steingruber, Austria. Christian is an Audio Engineering Society member, and has a few short, relevant comments to make about amplifiers he has seen and heard with the Quads, old and new. I have added some notations in yellow, and followed on with remarks on additional amplifiers that I know will work, and work well with the Quads.