It's' called optical out. Look in your manual for instructions (meant nicely) - it should be easy to follow.
Panasonic 60VT60 (cal by DNice)
Denon 5200 w/ Outlaw 2200 Amps (3)
Ascend Acoustics Sierra 2s F/R & Horizon w/ RAAL Center; Sierra 1s Surrounds; DefTech PM1000 Fronts, Ascend HTM-200s Top Middle and PSB S5 Rear Surrounds; Dual SVS subs
Oppo 103; Onkyo HD-DVD; Apple TV & Roku Stick
Atmos arrived on 9/30/2014