I have also owned many Pass, or Nelson Pass designed, amplifiers going back to the mid 1980's- and have found some improvements in replacing the beloved supplied power cord on some of them. I am currently using Audio Sensibility Statement cords on my XS150 monos - and was happy enough to go with them throughout the rest of my system. I will say - what I think made the most difference - was plugging them directly into their own dedicated 20A circuit.
