in our front room i currently have a denon receiver of some sort and crap speakers that came with a surround sound system years ago. I understand NOTHING about sound this is purely for the mrs as i don't even listen to music but what would be the best route do you guys who know more than me think for improving the sound quality (for films and music)without spending too much. Would it be centre speaker first or front l+r first? i have 0 clue about sound 
