Does an aftermarket power cord matters for Amp?


I am currently using the stock power cord for my VAC Avatar tube integrated amp. I have upgraded my cdp's power cord (given the trigger-down theory with source component) a while ago with a Synergistic Research A/C Master Coupler and had good results. I have been wondering if I should do the same for the Amp and question if it really does make a difference. If so, is it significant and worth the investment?
stevenkc
My first pc upgrade was two relatively inexpensive Sonic Horizon cable into my amp and preamp. The difference from the stock cords was quite noticeable -- more refined sound. I have since "upgraded" tp more expensive Michael Wolff cords. They make subtle improvements, but not as significant as the replacement of stock cords. The replacement of stock cords created a larger difference than when I subsequently added a Richard Gray Power Company 600.
Funny that member Jkphoto pushes Kubala-Sosna. When Jkphoto is the Kubala. Nice try.
After trying many P/C's from the Cable Co. I found the Shunyata Mojave's to be the best sonic match for my B&K mono amps.
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Thanks guys for all the good input and I will continue to read up. Any additional input is still appreciated.

Jab,
What power cord did you end up for your VAC amp? Would love to get another suggestion.