ESL's = single driver speaker. No crossovers and the best transient response there is.

jrhymeammo:
I always called it the credit card sound. Sort of plastic like. It may be the tweeter sections of the smaller models. The 1.6QR's have less of it. The true ribbons on the 3.6R's and 20's sound much better than the QR models. Also, if you turn them around and listen to the backs they sound a lot better. This works on all the Maggies I've heard.