Techniques are provided for providing 3D audio, which may be used in augmented reality. A 3D audio signal may be generated based on sensor data collected from the actual room in which the listener is located and the actual position of the listener in the room. The 3D audio signal may include a number of components that are determined based on the collected sensor data and the listener's location. For example, a number of (virtual) sound paths between a virtual sound source and the listener may be determined. The sensor data may be used to estimate materials in the room, such that the affect that those materials would have on sound as it travels along the paths can be determined. In some embodiments, sensor data may be used to collect physical characteristics of the listener such that a suitable HRTF may be determined from a library of HRTFs.