Hi Sogood51, pop away my friend!
we have to be careful here in describing what we are hearing in the presentation. The amps you mention are all ok. Nothing wrong with them. Trust me once you hear something like a Halcro you will understand. It adds nothing and is utterly detailed. It is the last word in faithful reproduction. Remember it has the honour of being the amp with nearly 0 distortion! No valve amp I know of can do that.
I dont want to be a valve amp basher as Iike most good ones have owned some great ones. But you will find in a full range set up, there is a "thud" like approach to low bass in comparison. Some recordings benefit from it, but its not real, its an artifact of the amp. The rest is down to taste but facts are facts