Kegger
R.I.P. 1/12/1966 - 6/1/2017
Actually no, in addition to the UL, (a little more is "needed" than just the UL)
On this schematic and others posted around here, and other places as well it is the resistor from the plate of the output tube to the plate of the driver tube.
If you follow it logically what you see is some of the output tube plate is fed back to it's grid, just connected to the other side of the coupling cap to block dc.
(It's an simple but effective way of getting a bit more feedback to clean things up without adding the output transformer in the loop, I prefer this method)
On my later builds of the same basic circuit it has been tweaked for "better" performance, I like triode, but for me this UL setup is a bit more refined output.
(having said praise for this topology, one should definitely experiment for ones self and see what they prefer to there ear and there gear/listening space)
On this schematic and others posted around here, and other places as well it is the resistor from the plate of the output tube to the plate of the driver tube.
If you follow it logically what you see is some of the output tube plate is fed back to it's grid, just connected to the other side of the coupling cap to block dc.
(It's an simple but effective way of getting a bit more feedback to clean things up without adding the output transformer in the loop, I prefer this method)
On my later builds of the same basic circuit it has been tweaked for "better" performance, I like triode, but for me this UL setup is a bit more refined output.
(having said praise for this topology, one should definitely experiment for ones self and see what they prefer to there ear and there gear/listening space)