Here's what you are doing. Cathode follower 6AS7 biased at around -30V Run 75V PSu with a choke load or 150V with a giant 15W resistor load. Bandwidth will be DC to light. Obtain a good (not botique) film cap for output. Don't even think about a 'lytic. e., http://nigeli704znd4.bloginder.com/profile