Shootout of Nos 6sn7 tubes

@dlcockrum Great info many thanks!

Another can of worms?  Anyone try mixing different styles of 6Sn7’s with success. I had a Raytheon vt231 T-plate that lost it’s partner due to bad noise.  On a whim I had just received one of my Ken Rad vt231 black glass and wanted ti try it out to make sure it was good and noise free.  Both tubes tested over 100% closely  matched.   Fired them up and  not expecting much but was  shocked how good it sounded.  Best pair I have rolled so far.  Looking forward to the second KR.  

@dlcockrum @shkong78 ordered a pair of Nos/Nib National Union 6F8G round plates and adapters.  They are branded Raytheon with identical construction as NU. I am using a Mullard GZ34 and Rca 6l6 bottom getter blackplates in my Supratek pre. Should be fun🤞

@tksteingraber IME, the KenRad VT-231 and NU 6F8G can sound a little closed in (lacking air and sparkle on top) with the Mullard GZ34 rectifier in my system. If you find that to be the case after becoming acquainted with them in your system, try a more lively rectifier like the Phillips 5R4GYS.

@dlcockrum thanks…that Phillips 5R4GYS is next to impossible to find and big💰.

Not sure my modest system is worth it and would benefit much from it.  I will keep it in mind though.  Have you tried other 6F8G’s? Other good ones in case I want to have other choices? 

@tksteingraber i was fortunate to buy two of the Phillips rectifiers back when they weren’t so pricey. Perhaps someone else on this thread can recommend another rectifier with similar sonics. For now, just see how you like the KR and NU with your Mullard GZ34…

I have not yet heard any other 6F8G tubes in my system. It is sometimes said that the other 6F8G’s (TS, Raytheon, etc) sound very similar to their 6SN7 counterparts with the NU being the exception, but I do not have first hand experience with the others.

I found this 6F8G thread informative: https://www.head-fi.org/threads/6sn7gt-6f8g-an-exploration-of-wwii-era-octal-tubes.890205/

Unfortunately, as always seems to be the case nowadays, the 6F8G models the author most prefers are unobtainium now (KR round plates and Raytheon dark glass flat plate).

I just broke down and ordered a pair of NIB/NOS Melz 1578s (the real ones $$$$). Will let you know what I think.