Opinions Please - New Prodduction Sophia EL34ST Coke Bottle

The Sophia EL-34-ST tubes are a revelation in my Unison S6 - easily 60%-70% better than the Tung Sol EL-34B's the amp came with in every meaningful parameter.  The Sophias marry the bloom and sweetness of NOS tubes with modern frequency extension and solid state caliber dynamics and bass punch.  There are no weak areas.  Have not compared them with Psvane or Gold Lion KT77. 

After more extensive listening I have found the blue Sophia EL-34 tubes to be a little too much of a good thing. In my Unison S6 they are bright on a significant number of recordings. For example, listening to the Ray Brown Trio's "Summer Wind - Live at the Loa" SACD, when Gene Harris gets into the upper octaves on the piano the notes start to sound metallic. I switched to a matched sextet of the Gold Lion KT-77's and they were similarly bright. I suspect that this result is unique to the Union S6 with its unusual parallel single ended ultra-linear circuit. Since the amp was voiced for EL-34's I ordered a matched sextet of the Psvane EL-34 PH tubes which are updated replicas of the legendary metal base Phillips EL-34's. These did the trick - all of the positives of the blue Sophia's without the brightness. In the Unison S6 these are the best power tubes I've heard.