Instead of expanding the qualities of the Performance series in a new model with Bluetooth technology, ULTRASONE have developed a module that turns every headphone in the Performance series into a Bluetooth headset. You simply disconnect the cable from your performance – and plug the SIRIUS Bluetooth module in its place. Enjoy your music via Bluetooth aptX technology with complete freedom of movement. The design of SIRIUS Bluetooth receivers is tailored precisely to the headphones of the Performance series. The strongly curved shape is based on the design of the headphones and hugs therefore precisely on their housing. Frequency of human hearing is transmitted. Thanks to the S-Logic Plus technology, the natural spatial sound is aimed for in order to locate instruments with precision.