Marantz NA6005 Owner's Manual

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Connecting to a device with digital audio output connectors
Use this connection to input digital audio signals to this unit, and convert the signals for playback using the D/A converter of this unit.  (v p. 81)
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OPTICAL
OUT
CD transport / 
Digital device
NOTE
0 Linear PCM signals with a sampling frequency of 32 kHz, 44.1 kHz, 48 kHz, 64 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, or 192 kHz can be input into this device.
0 Do not input non-PCM signals, such as DTS and AAC. This causes noise and could damage the speakers.
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