Charles1dad,
Yes, I think the Classic Audio speakers are bright and mid-bass is thinner than my ideal. OTL amps, like the Atmasphere amps, and field coil speakers, have as their primary area of superiority, incredibly lively sound--very fast and dynamic and immediate sound. But, pushed too far, this sound can be edgy and brittle; it is a matter of taste. By contrast, the stacked Quads in the Emia room and the field coil system in the Deja Vu room were also quite dynamic and immediate sounding (though not as extremely so), but the initial attack of musical instruments sounded more natural to me on those systems so that the sound was smoother and more natural while not being muddy and slow sounding. It is a matter of tradeoffs and priorities.
The Zu speakers also have a very dynamic and immediate sound. As most shows, they are matched to high powered amps to emphasize this strength by being played at high volume levels (it is startling to hear, but also tiring). They really can be made to sound much more refined and relaxed, but, I suppose, at shows, the idea is to grab attention.
