I tried Citadel 1.5 on my S5.4, they were too bright for my system, bought a pair original Citadel, very happy!
Mark Levinson 436 vs. Theta Citadel monoblocks
I'm thinking about to get either one of these to match Dynaudio S5.4, I know they are both good amps, can't decide which is better for S5.4, I like a slight warm sounding, but still with details, big sound stage, not too forward not too laid back, any members had them before? thanks!