[Escott1377]

Is anyone familiar with this tube?  You can sub for a 12sn7.  Is the sound any different?

Thanks in advance -

[LarryD56]

From what I've read and also by having a half dozen of the 1940's smoked glass RCAs I haven't heard any difference from the regular smoked glass 12SN7s. I believe the 12SX7s were supposed to have tested at tighter/more evenly balanced tolerances than their standard 12SN7s.

Larry D.

[isaacc7]

Everything I have read says that the 12sx7 was a 12sn7 with lower microphonics. I have a pair that are labeled as GE that sound remarkably open and clear when used in my preamp. They seemed to have had a bit of hype around them a decade or so ago. They are worth trying.