This is an unpopular view on the Wam, but I'm trying valve monoblocks and a valve pre at home (the Icon Audio 845 and the new LA5preamp) and I'm just not getting the results I'd hoped for. I suspect the problem is the speakers, which I think are too difficult for the 845s to drive accurately.
The speakers are a true 4 ohm load across most of the frequency range and using the 845's 4 ohm tap produces a richer sound and fuller bass than the 8 ohm tap, but at the expense of treble. There is a clear roll off in the higher frequencies that makes violins, pianos etc, sound flat and a little too dull (a recent review noted a steady roll off from 8kHz, reaching 3dB down with the 4ohm taps). When the 8ohm tap is used the higher frequencies are better, but the overall tonal quality seems to become compressed and strained.
I'm coming to the conclusion that SS amplification is the way to go. I went to a performance of Bach's B Minor Mass last weekend, played by an excellent baroque orchestra and choir in a wonderful church acoustic and it grieves me to say that the overall sound of the valve kit is considerably farther from the live sound than my humble Quad 909. I can see why people fall for valves as the sound is unfatigueing, but it's not as good a representation of the 'real thing' (IMO). Should I give up on valves?