Abstract: A headset includes: a hollow housing (10) to be worn at an ear of a user; a cylindrical ear canal insertion part (12) that is a portion of the housing (10), and that is provided at a portion of the housing (10) at a side of an ear canal; a driver (14) for signal output, provided at an interior of the housing (10); a microphone (18) provided so as to collect a signal propagating at a second hollow part (16A), extending from inside an ear canal insertion part (12) and different from a first hollow part (12A) inside the ear canal insertion part (12), through which a signal output from the driver (14) propagates; and a computation unit (22) configured to measure a temperature inside the ear canal based on a collected signal collected by the microphone (18) at a time when a measurement signal is output from the driver (14).