Hi Frank. Congratulations on your new amp. I'm glad you enjoy it. I did some research on the Boulder, and heard both the 1060 and 2050 in other systems. The Avalon/Boulder combination seemed worthy of consideration. I did not care for either amplifier, though.
I did have the Karan, and have heard Dartzeel. But no, I have not heard some of these boutique European amplifiers such as FM acoustics, Goldmund, Gryphon, Vitus, or Solution. These amps are very difficult to demo, often do not have tremendous power, and while I am not afraid to shovel money at my stereo, carry price tags that make me wince. For the foreseeable future, I don't have an interest in other amps. The Pass continues to exceed expectations. Right now, I am working for cables, and have made some major discoveries. We can take this over to my system thread as not to divert Wslam's discussions.