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The DAC-50 is an optional digital input board that supports a broad range of digital sound sources and is equipped with a high-precision MDS type D/A converter for optimal sound quality. The converter uses AK4490EQ chips from Asahi Kasei Microdevices in a double parallel configuration per channel. Installing the board in a slot on the rear panel of a supported Accuphase component provides direct input capability for signals from digital components for high-grade playback.