STA339BWS 2.1-channel 40-watt high-efficiency digital audio system Sound Terminal® is a highly integrated audio system that can be configured as 2-channel, 2.1-channel or 2-channel plus 1 PWM output. It supports multiple audio input formats, including PCM, I2S, DSD, and IF, and has multiple functions, including digital audio processing, power amplification, audio presets, etc.