Kurt tank,
You are correct. I forgot it's there tube amps I was thinking of. Yes I've had most of the good highend amps. They are all good in there own right. I will never fault any of them but they all sound very different. I was a big tube amp guy but some of the solid state amps these days are very very good like Boulder and Goldmund, there a reason why those too are so expensive. A lot of it depends on your speakers when choosing an amp. I think CAT amps are amazing but they don't work for me because of the amount of tubes and the heat. You have to find the amp that works for you. The only amp's I really didn't care for was the Ayre MXR and Dartzeel. Those are way overpriced IMO.
The K1xe is still one of my all time favorite preamps. It works well with most amps but just make sure you use shorter cable length's with it. IT doesn't like driving long cables and you have to use it balanced.
