JohnsonWu, I just don't agree with your assessment of the sound that the older ARC amps exhibit. My D70Mk2 has wowed all of the a'phile group that has heard it in my system. So much so, that one of the group traded a BAT VK75SE for a pair of M100's ( with the same wonder caps) and never looked back after he heard my ARC/CAT set up.
I'm sure you are aware that ceramic tweeters will exhibit glare and hardness with aplomb. The same can be said, to a slightly lesser extent, for the beryllium tweeters in your Utopia's. A hard dome can be bright and exhibit glare IF any of the upstream components are at all bright...speaker cables, preamp, front end, amp etc.
I believe and i think many others are beginning to believe also, that a silk dome or a ribbon is far less likely to exhibit this behavior than a hard ceramic or metal dome. Which, if I'm not mistaken is one of the reasons that Dave Wilson chose a silk dome for his top of the line speaker, the Alexandria XLF. I guess when it comes to this discussion, YMMV.
I'm sure you are aware that ceramic tweeters will exhibit glare and hardness with aplomb. The same can be said, to a slightly lesser extent, for the beryllium tweeters in your Utopia's. A hard dome can be bright and exhibit glare IF any of the upstream components are at all bright...speaker cables, preamp, front end, amp etc.
I believe and i think many others are beginning to believe also, that a silk dome or a ribbon is far less likely to exhibit this behavior than a hard ceramic or metal dome. Which, if I'm not mistaken is one of the reasons that Dave Wilson chose a silk dome for his top of the line speaker, the Alexandria XLF. I guess when it comes to this discussion, YMMV.