Shuguang Black Treasure CV181-Z

Old discussion, but thought i would elicit feedback - I want to replace the stock 6SN7 tubes in my preamp, but I'm unsure if I should go the NOS route or the "new Chinese" tubes? I'm leaning towards the Black Treasure CV-181-Z, but I would appreciate feedback from anyone who has had the BT tubes in a preamp for any extended period of time. At the prices being asked of these (and solid NOS tubes) I don't want to head down the wrong path - very expensive to recover from the wrong decision. My other option would be 1940s Sylvania black base (non-metal base) NOS tubes.

Thoughts . . . . ?

I have a pair of the BT CV-181-Z and I prefer the Sylvania's of course that could change depending on preamp. The manufacturer of my favorite preamp just changed the circuit and added a jumper so that I can use 6NS7 or 12SN7's. I have found an abundance of NOS 12SN7 tubes at far lower prices. I got a great deal on 40's Sylvania bad boys and Tung-Sol Black Glass Round Plate Oval Mica.

Hi msgtrlsmith – I can't speak to a comparison with Sylvanias, but I can tell you that the Black Treasures trounced the gold pin EH 6sn7s that were originally in my Blue Circle...to the point where it sounded like a different amp (in a good way): better sound staging, more air, sweeter treble, more precise imaging...and on and on. In every way that matters to me, the  BTs were noticeably better – as they should be, for 3X the price of the gold pins. But I've never regretted the purchase...it was a no brainer for my system. Just be aware that the BTs are significantly larger than stock 6sn7s...make sure your preamp can accommodate. I had to have my chassis altered to enable me to use them...but it was worth it. 

Another strong endorsement for the Black Treasure "Z" tubes. More musical, dimensional, and transparent than the Sylvania Chrome Domes and Sophia 6SN7's I used prior in my MW 5400ES.

Dave