On the control module, slide the power switch to ON. The headphones will turn on in noise cancelling mode, which reduces most sounds around you.
Note: When the power is off, the headphones will still provide unpowered audio. For the best audio quality, turn the power on.
on the side of the remote, press the mode button to switch to aware mode. this allows you to hear some sounds around you, such as traffic.
You can connect your Bose® QuietComfort 20i headphones to the standard 3.5mm headphone jack on most smartphones and portable devices, such as an iPod®.