"Hi Phil, Paralleling tubes is easy: You simply connect all components in parallel. That is (for a triode): 1.) Parallel the heater connections 2.) Parallel the cathodes (if they are wired seperatly from the heaters) 3.) Parallel the grid pins 4.) Parallel the plates (anodes) Thatīs all. Toob greetz from Germany, Reinhard " Would be a good idea to add small (say 47 ohm) resistors in the separate grid leads to prevent VHF parasitic oscillations. Ed