Shootout of Nos 6sn7 tubes

@tksteingraber 

6F8g tubes tend to sound fuller than regular 6sn7.

Thus it may depend on your system and taste which one to choose.

Thomas

@tksteingraber I have found that the National Union 6F8G round plates are very special tubes in my Supratek Syrah. I also have the NU 6SN7 round plates and the NU 6F8G sound better in every way. Also have Tung Sol VT-231 round plates (transparency kings), KenRad VT-231 staggered plates (bass kings), Sylvania T-plates, Baldwin flat plates, Sophia Electric, and Shuguang Treasure CV181-Z and the NU 6F8Gs are my “go to” tubes.

Keep in mind that the Supratek power supply’s rectifier tube paired with the output tubes has a significant influence on the sound (I like the Phillips 5R4G rectifier with NU 6F8G while the Mullard 5AR4/GZ34 Fat Base rectifier pairs better with the TS round plates IMO), so some mixing and matching of rectifiers is important.

Re: Raytheon 6F8G T-plates vs flat plates, the T-plates are much easier to find but the flat plates (scarce as hen’s teeth) are said by many to be significantly superior sonically.

@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.