I'm really new to iMacs and 5.1 systems, and I wanted to know how can i connect the Z-5500 logitech 5.1 speakers to an iMac...can I just plug them in into the optical-out port? I want to know all of this before i order my system from the internet, and no i don't have any store nearby where i could check neither of the systems out, so this is the only way I can know how to plug them in...thanks, migue.