Oldrider,
Congratulations!
Your New piece of equipment has two formats, SACD and Redbook CD. You should break the player in by playing both formats equally for a minimum of 100 hours to hear the best music reproduction that this fine player can provide.
I would also suggest that you do not use the stock power cord. I will give you some recommendations if you send a PM. (Yes I have owned the Marantz SA 15, SA 11, SA 8001).
For the contrary posts above relating to "break-in", IMO/E,
Mfgr's do not put it in a manual because as some have stated they like to hear the player mature.
* Some may not have the hearing acuity or the equipment to hear improvement.
* It is not a necessity.
* The unit will not send you running from the room with your ears on fire. (it sounds Okay out of the box).
* Mfgr's are not in the business of telling customers "what or when to tweak their equipment". That is a personal decision best left to the individual.
* If you cannot hear any differences the Mfgr's do not want to be in the position of planting that possibility in your head. Too subjective and none of their business.
Opinions may vary as this is a forum and all points are open to friendly debate.