I have to eat a little crow.
I posted earlier that I preferred my Supratek linestage to the LS due to an added dimensionality and warmth that tubes offer with all other thngs being equal between the two.
Well, reading this threat spurred me to put the LS back into my system for another listen. I'm glad I did.
The first time I compared the two I simply connected the LS to my system with it sitting on a cardboard box on the floor. This time I went to the trouble to take my Supratek out of my system and I put the LS on the same shelving and footers I use with my Supratek.
This time I must say the LS is slightly more transparent, with equal slam, warmth, tonality soundstage width, etc. The only area that may be up for grabs is on some recordings the soundstage is slightly more forward with the Supratek. I'm not saying that is a better thing, but rather a simple difference.
To be honest, the two are so close that I have to really, really, really try hard to tell the two apart. I listened to several recordings that I know exceedingly well and I swear had I not known that I took my Supratek out of my system, I don't think I would have noticed.
The biggest problem I have with my Supratek is getting good 6SN7's, both NOS & current production, that don't have issues at some point, i.e. microphonics, loud hissing (not typical tube noise), whistling, cracking & popping, etc.
I just purchased a pair of the new Shuguang Treasure CV181-Z to try. They sounded as good or better than any NOS 6SN7 I have ever tried, including TS RP and 52 Bad Boys. However, one went extremely microphonic between 30-40 hours. As much as I love tubes, they frustrate the crap out of me at times.
So, I am sticking with the LS for the time being. I tried to be as objective as I could between the two preamps and when comparing apples to apples (same shelving & isolation) I have come to the conclusion I don't think I could tell them apart in a blind test.
Thanks for an incredible product George at an unbelievable price.