DT03 HiFi Audio Player Bluetooth/USB/Optical Fiber/Coaxial/AUX Input to 5.1 Channel Preamplifier Audio Decoder. - Model: DT03. The design of the preamplifier based on the large-scale integrated circuit QS7785PF is a single-chip surround sound processing large-scale integrated circuit produced by the Audio Technology Laboratory Surround patented technology.
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