The NTI 4K-HD-SCALER is an Up/Down scaler with Audio Extractor that is designed to up-scale a 1080p HDMI signal to UHD 4K (3840x2160) 4:4:4 60Hz or down-scale 4K (4096x2160 or 3840x2160) to 1080p. The audio signal is duplicated on the digital optical S/PDIF Toslink audio output and 3.5mm stereo audio output for separate processing on an external amplifier or AV receiver.