Go ahead and remove it. I don't see how it can have any affect upon the SS high level stage. The SP14 is a curious design using one dual triode for the phono stage and transistors for the rest.
ARC SP-14 tube question
I am currently using an ARC SP-14 preamp, but both turntables are going to line level inputs, the internal phono pre is never used. Can I safely remove the tube which creates a surprising amount of heat to hopefully prolong the life of nearby components inside the preamp or would no load in the circuit cause any problems? Thanks in advance.