Only for owners of ARC SP 16

I have just acquired an ARC SP 16 as replacement for an ancient ARC LS2B.The rest of the system comprises a Bryston 14 BST,Arcam FMJ CD 23 and B&W CDM 9NT speakers.
My query is whether any SP 16 owners have experienced any audible improvements after replacing the factory supplied power chord. I should add that the SP 16 is barely a few days old and is a long way away from being broken in.
After a couple of days, I replaced the factory supplied power chord with a $350 Transparent Superlink power chord I had used extensively with one of my earlier preamps the Bryston BP 25. Now wonder of wonders, the system sounds much better with the factory power chord. There is greater transparency and detail which is ever so slightly masked with the Transparent chord. Has anyone experienced anything similar?
Overall, this may sound a wee bit premature but the SP 16 is a brilliant preamp.Straight out of the box it has brought a certain ethereal quality to the music whether Norah Jones or Pink Floyd.
Many thanks for your patience and time.
Audio Research equipment is generally highly revealing of power cord changes. Transparent cords tend to be dark; in my limited experience of having an SP16 in my system on trial it's also somewhat rolled off and "tubey", at least in comparison to other Audio Research pres. I'd try a better matched cord. I've found that BMI cords work really well... you might want to find a used Shark on Audiogon and see what you think (there are a couple available now at prices that are steals)-- it's my own best match to my SP9 MK III and its tonal qualities should complment the SP16 well.
Many thanks.I reckon that I will stick to the ARC chord for a while.Don't want to upgrade everything at one go...might lead to the ultimate audiophile nightmare...everything's perfect and might die of boredom.