The 6CG7 EH is a medium-mu, dual triode; basically, a 6SN7 in a 9-pin envelope. It offers much of the low noise and smooth sound of the original 6CG7 and 6FQ7 from the 50s and 60s.
The old Tungsol name is back. This new production 6SN7 from Russia. Definitely an upgrade from the other 6SN7s in production.
One of the best sounding octal tubes ever made, the 12SX7 is a direct replacement for the 12SN7. (Introduced in 1946, the 12SX7GT was created to work under extremely low-voltage operation in airplanes.)