Quality Stereo sound throughout home?

I want to have several sets of speakers in a couple or my rooms and want them to all run off a rotel RMB-1077 or similar but I want the best signal I can get. I know long spans of wire will limit the sound quality and I am ok with that but how can I add a volume control to each room without much sound quality loss? How can I split the pre/pro outs without getting signal loss? I plan on having this hook to my mains in the living room, a pair of smaller bookshelfs in Master bedroom, bookshelfs in the computer room, and a set of outdoors or possibly the garage. I prefer to have the source in one location or be able to use multiple sources from the one location so I can have the higher quality source and identical output through home. Right now I have a yamaha 5760 but it's on the upgrade plan soon... I'm assuming the source will be multisource capable (most likely a parasound C2). If I do this I will use balanced inputs for my mains and unbalanced for the rest. I know I could use impedance-matching volume controls but won't I get some sound degredation with these? Is there a better solution knowing that I want each channel powered by 1 channel of the RMB-1077? Would this be stereo? I haven't had the chance to look at the volume controls in person but I assume mono vs stereo which I want to avoid. If I can only get mono I may just do in ceiling but then is there an easy way to convert stereo to mono?

Thanks in advance!