I just (yesterday in fact) put a new Pangea AC9SE four meter powercord in place of a pangea AC9 two meter powercord from dedicated outlet to my Furman REF20i power conditioner.
(I bought the cord to place from PC to amp, but thought I would break it in, at wall to PC.)
The difference makes me intend to leave it where it is.
The increase in dynamics, attack, PRAT, and mid and low bass was noticable.((('as if' no conditioner in place for negatives caused by them, yet all the positives stayed..cool)))
Not dramatic, but pleasant suprise. considering the jump was from a single Pangea AC9 to a AC9SE (twice the price cord) ((Also the longer length may play a part???))
So much so that i am leaving the cord where it is. And am going to get another for PC to amp.
The cord cost me $300 after rebate. My Conditioner is a retail $3,500. and amp Bryston 4B-SST2 $5,000. Speakers Magnepan 3.6