Please suggest me a 5.1 speaker system to connect it to my Sony 32EX720.I am using airtel HD dth.Can i get true 5.1 effect if i connect it through RCA or 3.5mm jack.I have shortlisted Logitech Z506.Will it give true 5.1 sound.orPlease suggest me a cheapest 5.1 Speaker System with optical input.I need speakers under 5k.