Silky and soft highs: product of coloration?

Hi folks this is a bit controversial topic. I know some amplifiers (and some very expensive ones too!) have a very silky and soft presentation of the (upper) treble. I'm wondering if this silky presentation can be considered as a hallmark of quality for amplifiers or rather a sort of coloration that makes the upper treble soft and "pretty". In my opinion I can divide amplifiers in two groups: one group (the largest) with "ordinary" treble response (not very pretty) and the other group that consists of only a handful of amplifiers (both solid state and tube) with a refined and silky treble. The contenders within this last group are alas too expensive for mere mortals. This brings me to another question: is such a refined and silky treble only to be had with megabuck amplifiers?
I consider the Anne-Sophie Mutter recording "Carmen Fantasie" as the ultimate test recording for treble sweetness. If the amplifier sounds just "ordinary" with this recording (especially where the violin plays in the upper register) then the amplifier is not "refined" enough.

Chris