This disclosure related to an audio unit of a head-mounted apparatus. The head mounted device includes a support structure with at least one side section with least one audio unit. The audio unit is transmits a first signal and a second signal. Either the first signal or the second signal is directed toward an ear of the wearer of the apparatus. The first signal may be an in-phase audio signal and the second signal maybe an out-of-phase audio signal with a 180 degree phase difference. Alternatively, both the first signal and the second signal are in-phase audio signals. The audio unit may operate in one of two modes. The first mode includes the first signal being an in-phase audio signal and the second signal being an out-of-phase audio signal. The second mode includes both the first signal and the second signal being in-phase audio signals.