The PRE5 preamp uses the most advanced Bluetooth standards that support the aptX audio transmission protocol. Bluetooth is not all that the PRE5 has to offer, the preamp allows you to use up to 8 different signal source connection options. The PRE 5 is also equipped with a high-end built-in DAC, which allows you to decode the signal via: AES/EBU, Optical, Coaxial, BNC, USB and Bluetooth.