[ched999uk]

Getting some HD558 for Christmas and wondering about a Fiio E17 to provide better dac and amp. I intend using the combo on my desktop pc, small netbook pc, and, in my cinema room for connecting to the optical out from FreeSatHD (Humax FoxSat HD), FreeviewHD(Smartbox 8320hd) , Bluray (cheapy one) and HD DVD (Tosh EP30) player as my surround amp doesn't have a suitable output.
 
The E17 has the appropriate inputs but will I notice a difference in sound quality from FreeSatHD and FreeviewHD boxes via optical outs?
 
Thanks