In article .com,
wrote:

Or you could use a different tube for the output stage.

do you think the 6072 makes a poor follower? it'll just be driving the
5 or 10k load of an AD converter, and i don't plan on using long cables
between the two. do i need a higher current tube, like a 12AU7 or
something? since i'm modding, i'm trying to minimize the
pain-in-the-ass factor, and also not bludgeon the PCB too much. the
preamp used 12ax7s before.

I don't know, I never did the math on the 6072. But if you look up the
follower section in the Radiotron Book, there's a method for calculating
basic linearity from the load lines, and there's a formula for figuring
the effective output impedance with a given cathode resistor. Your whole
goal is to balance voltage swing with output impedance and get the best
combination for the device you're using. My personal feeling is you
probably want the load to be at least four or five times as high as the
output impedance of the stage.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."