Can flexible power cables sound good?

Sure there is. 12g zip cord from Monoprice works very well and if you hide it and tell people you have a $10,000 speaker cable they will believe it. Cheap and the fidelity is great. The only thing it lacks is bragging rights.

Shunyata has flexible cords as options in their line. Excellent power cords. 

Why not just email PS Audio directly. They will help you!!!

Audiophile sites are populated by wonderful people who happily spend hard earned $$ on equipment from vendors who have demonstrated the ability to provide awesome fidelity, well over 100dB of S/N ratio and vanishing low THD from their equipment.  The engineers for vendors can clearly do digital and analog magic with electronics, based on an understanding of solid state (and vacuum tube) design principles.

Think about this:  Are these same engineers not competent to build power supplies into their equipment to provide nice pure, regulated DC voltages to the same electronics?  These engineers know full well that power lines are loaded with noise and are subject to significant voltage fluctuations.  Really, they do know that.  They actually do know how to design power supplies to filter out all that crud.

There is nothing that a 6 foot super-voodoo, magic-sauce-included power cord plugged into a wall outlet can solve that these engineers haven’t already anticipated and solved as part of their power supply design.  Really.

The vendor provided you a power cord with your equipment that is perfectly sized for their equipment, knowing full well that at some point you will plug it into a wall outlet.  Think about it.  Spend your money somewhere it will actually improve your listening experience.  Of course it IS your money.

Caveat Emptor
jrh

Not sure about Blah, blah, honk, honk................................but Yeah
Audio Envy!!