ECC804
The ECC804 has some amazing characteristics thanks to the relatively low
mutual conductance. It provides the designer with the perfect phase
splitter/buffer amplifier because both of the triodes are perfectly
matched and have identical characteristics in every way. Further to
this, You will find a shield between the two anodes reducing crosstalk
to a bare minimum. Providing this shield is negatively grounded it will
out perform many tubes in the same gm range by far.
Please feel free to download the datasheet free of charge 
