Various implementations include headphone systems configured to adapt to changes in user environment. In some particular cases, a headphone system includes at least one headphone including an acoustic transducer having a sound-radiating surface for providing an audio output; a sensor system configured to detect an environmental condition proximate the at least one headphone; and a control system coupled with the at least one headphone and the sensor system, the control system configured to: receive data about the environmental condition from the sensor system; and modify the audio output at the at least one headphone in response to a change in the environmental condition, wherein the audio output includes a continuous audio output provided across a transition between environmental conditions and is configured to vary with the change in the environmental condition.