The cannen is a D'ni music recording and playback device. It consists of a small controller and speaker atop a stand that is between 3 and 4 feet tall. The large cylindrical button on the top of the device begins playback of a stored audio clip. While the device is clearly meant to serve as a recorder as well, the mechanism for activating that functionality is unknown. There is also a five-pointed knob on the front of the device, beneath the speaker grill. Its purpose is also unknown, though it may control the device's output volume.
Explorers can add a cannen to their Relto by collecting the Relto page located in the Great Shaft. Once added, the cannen appears in the explorer's hut, on the left side of the entryway (facing out). By default, the cannen will play the "Gehn's Theme" track from the Riven soundtrack while the Relto page is active. Explorers can also add the Kadish Gallery music to the cannen by interacting with the cannen on the upper level balcony of Kadish Gallery in Ae'gura. Once the Kadish Gallery music has been added to the player, it will cycle through both tracks in a continuous loop.
In the offline version of Uru, the cannen plays a clip of the music used in Uru's launch trailer. It can also play back any .OGG or .WAV file placed in the "My Music" folder inside the game's Program Files directory.