The RK34 is a double triode, with dual anode caps and a single cathode. I ran one sectio for each channel and biased the cathode with 4x red LED's run to their 20 mA limit.

It is a nice looking valve ST shaped and ~816 sized. UX7 base. I was worried on an intellectual level at running both channels through a common cathode. I noticed nothing out of the ordinary. Sounds pretty good too. I was pleasantly suprised at its sonics. Neutral, like a 6SN7, yet with more body.
regards,
Douglas