You can stream audio from Apple TV to AirPlay-enabled speakers if they’re connected to the same network.
On Apple TV, do either of the following:
Press and hold on Apple TV, then go to Video and Audio > Audio Output and choose the speakers you want to use.
If you select AirPlay-enabled speakers as your temporary audio output, home cinema sound and navigation clicks are not supported and your speaker selection resets after Apple TV is put to sleep.
You can see a full list of Airplay-enabled speakers on the Calibrate video and audio on Apple TV