Newbie Audio question

[king2440]

Hey guys well when it comes to picture, im really up to date and know the basics...but now with all the new audio gadgets, i've realy lost ground.

Pretty much my question is: the reciever I have is a Sony STR-K6800P
http://cgi.ebay.com/SONY-STR-K6800P-...ayphotohosting

That's it right there...dang i bought that for a ton of cash a long time ago, but anyways what's the best sound i can experience with that reciever? Right now i have it hooked up to my PS3 via optical...is that the best I will get?

I believe it is 6.1 surround which i currently have...if im not gonna get the full experience, any chearp upgrades? (college student salary here by the way)

also im sure there may be a post, but what exactly is loseless audio and the benefits of it?

sorry for the newb question, but after having my BD player for over 2 months, im thinking i can get a better SQ.

thanks!