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Fostex HP-A4 24-Bit Digital to Analog Converter/Headphone Amplifier$399.99
It features a front-panel 1/4" stereo headphone output, rear-panel stereo RCA outputs, and optical S/PDIF I/O. The HP-A4 has 2 gain staging levels, allowing you to boost the output of the amp by 10dB without needing to touch the volume knob. The selectable filter allows you to cut-off lower frequencies if desired.
A USB cable and 4 rubber feet are included.