Upgrading mains, yes - a dedicated spur can make the sound better, but only after you've done everything else possible to ensure set-up, positioning, etc, is optimised. Whether it's worth the extra expense kind of depends on what you mean by a mid-range system...
yeah true. it will be my last upgrade and i will try a selection out. i hope i can borrow from a shop for a deposit. bymidrange i mean monitor audio br5,s, £350 cd player, £450 surround amp and £1500tv and blu ray, i guess that is really the higher end of a budget system-- not quite midrange is it.
But i am talking a dedicated ciircuit from the fusebox/conxumer unit just to feed your audio home cinema system, not just different cables from wall socket to piece of equipment.