A HDAV Adaptor is a cable that plugs into the A/V socket of your Xbox 360 Console and provides audio output via Phono Stereo or Digital Optical outputs. This allows you to connect a Turtle Beach Headset to your Xbox 360 when you are using an HDMI Cable to transmit the picture and sound to your display.

Do I need a HDAV Adaptor?

If you connect your Xbox 360 to your display via HDMI you may NEED
a HDAV adaptor to connect a Turtle Beach Headset:-

To Connect any Turtle Beach wired stereo headset to an original Xbox 360 or a Slim
You will need a HDAV Adaptor unless your display has stereo phono audio output.
(Please refer to your TV's instruction manual for further information).

To Connect a Turtle Beach headset via Optical to an Xbox 360
You will need a HDAV Adaptor unless your display has an optical output.

To Connect a Turtle Beach headset via Optical to an Xbox 360 Slim
You will not require a HDAV Adaptor as your Xbox 360 Slim has an optical output.

Click the image below for a video on connecting your headset: