Audio Research SP-6 captive cord.......

Would changing a captive Audio Research SP-6 model preamp cord to an "IEC" change the value of the preamp? Presently, I don't have any intentions to upgrade to another preamp but was wondering how much better the preamp might sound if I could try different power cords.Has anyone who owned a SP-6 changed the captive cord and did it accomplish much of an improvement? I have a tech who can do the change with no problem.

Thanks
Chuckie