Best tube rolling options for VAC Ren MkIII preamp

I have read most VAC threads on Audiogon and pieced together some information on tube rolling for VAC 300.1a and VAC preamps (Renaissance Mk III is what I own). Was hoping to get in one thread others' experience/POV/advice on what the best tube swapping options have been for their VAC gear, or other high end amps/preamps that take similar tubes (e.g., 12AX7, 12AU7, 6sn7), or if stock tubes from VAC ended up being the best choice. Thanks in advance for any insights. If I'm missing an definitive thread on this pls redirect me.
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The Shugaung Black Treasure 6SN7 equivalents sound excellent in my Ren 30/30 amp.
I agree with Jab. I have tried many different NOS versions in my VAC pre and each brought something nice to the presentation. Every time, though, I have found myself back with my VAC sourced tubes. The balance across the board is better IMO.
I will say putting Ken Rad 6sn7s in the two outer tube locations of the 300.1a gives energy and low end presence without taking away from pristine, smooth clear highs this amp naturally offers.
did some swapping this weekend. nothing matches stock tubes for clear clean highs on vac 300.1a. anyone want to buy barely used (1 hour) 2 matched pairs of Ken Rad 6sn7s drop me a line.

I have some Ken Rads, are they all the same? Can you send me some pics to
Will do, Mr. Wig.

How can you come to a conclusion on a NOS tube after 1 hour of listening? I guess you don't believe in break-in period? :-):-)
Not on a nos tube. I didnt need more than an hour with stock input tubes to appreciate their sonic character. Unlike components and cables i havent heard much change over time with tubes even my sophia 6sn7 tubes. Maybe my ears are not evolved enough. :-)
Podeschi, I have to disagree with you on this one. In my experience I have not heard one tube that doesn't change over time sonic wise, normally 50-100 hours so I feel you are missing out big time. Heck it tacks 40 minutes for most tubes to be stabble!

My 2-cents worth anyways
My Recently added seimens 7308s into my Ren sig mk2a made a huge. Difference - deeper and tighter bass, more extended highs, etc. Overall a much better, well balanced sound. Wouldn't have believed it out of 2 tubes.

Added Black treasures as the front 4 tubes for each 300.1 about a year ago. Got slightly sweeter,more extended highs.

Good luck.
Hi Fplanner2010, I received mine and just installed them. I will share my results in time.
Great!! Although we have great VAC in common, our systems
Are quite a bit dissimilar since our speakers are so different. I heard a difference immediately, that has just kept getting better at about 40 hours so far.
Ok i clearly need to make a second run at this! I would let the amp warm up for an hour before critical listening but didnt burn in jan, ken rad etc input tubes. I will do that and give it a second listen. Part of my impatience was tied to others' comments how it was hard to beat vac stock tubes.
I should add...what i find hard to replicate is the open extended airy highs of stock 6sn7 tubes
Hi Fplanner2010,

okay some initial thoughts with these 2 tubes in my pre.

Most defiantly you can hear a difference from the get go, yes I agree the bass is tighter and deeper, highs are extended and are actually clearer. Would not know this was possible until having placed such in my pre and actually hearing the differences in person. The floor noise has dropped also, more focused.

Will put in some more hours and then place back the original ones to compare, amazing what two tubes can do :-)

Thanks again!
Dev- Glad you like them!! I couldn't believe it either, but there is no substitute for hearing them yourself in your own system.

I have about 50 hours on mine so far and they are still improving - probably the best "bang for the buck" improvement I've ever made to my system. :-) Enjoy!!