I'm a bit late I know. I've been rather busy this weekend
In addition to dynamics I should have pointed out that a good valve amp can do the requisite leading edge attack/transient response to really satisfy with rock programme.
I come from a very flat earth background having familiarised myself hands-on with the entire Olive Naim range a few years back. In my own system I've owned a Naim CD5 (with and without a Flatcap) and a CDX both into quite a few Densen boxes for amplification including the B-330 power amp.
www.densen.dk
PR&T is very much a pre-requisite for any system of mine and going to valves for me was about building on existing virtues rather than a sea change from raw edge excitement to pipe 'n slippers. I love the Naim sound but these days nothing below a CDS 555/NAC 552/NAP 500 would do it for me as everything below that level sounds a little too rounded-off for my tastes.
Either the TD/AOS amp of mine is exceptional value for money or Anthony is a genius. Or both. It has already been described as being "like a very good transistor amp."