The SQ-ADC-2121 is an Analog-to-Digital audio converter. It is designed for SEQUOIA Signal Processing Platform. The SQ-ADC-2121 converts a group of analog stereo audio inputs into two balanced AES3 digital audio outputs and two unbalanced AES-3id digital audio outputs. It supports synchronization of the outputs according to the input reference clock signal or digital audio signal. The SQ-ADC-2121 indicates input stereo audio level through the LED indicator at module edge. LED indicator on module edge shows the status information of signals, and the ADJ switch can adjust the parameters manually. Module with independent rear panel can be used in SEQUOIA 1RU or 2RU frame. The SQ-ADC-2121 supports the function of network monitoring of Sequoia series platform. The module can be controlled and monitored via SEQUOIA network control module and SQ-MASTER platform control software.