Singxer SU-2 USB Digital Interface DSD1024 Femtosecond Clock Interface Audio Interface SU2 Independent Clock HIFI SU2Product Description The SU 2 digital interface is a high performance USB digital audio interface. The microprocessor with the latest ARM Cortex M4 as the core is used as the main control of the USB data part. SU 2 uses a self developed ultra low jitter clock system (ACCUSILICON's AS 318B series, which achieves ultra low jitter at the femtosecond level). A large capacity FPGA serves as the digital audio data processing core and has a standard USB2. 0