I am looking to upgrade the sound from my PC. I wish to bypass the sound card of my computer by plugging in a digital-to-analog converter (DAC) in a USB 2.0 port. I've learned I can stream digital audio that way by selecting my DAC as the default audio output device. However, the DAC I am considering also can stream data from the digital optical output on my PC to the DAC. A tech rep for the DAC told me to stream music from both the optical output and the USB port alternatively and see which sounds better. However, for the DAC to utilize the digital optical jack it must be set to pulse-code modulation (PCM) stereo output.
The way the analog-to-PCM conversion is done is via a process called sampling. As mentioned above, analog sound moves in waves, while PCM is a series of 1's and 0's. In order to capture analog sound using PCM, specific points on the sound wave must be sampled (frequency). Jan 15, 2010 Standard SPDIF/Toslink only supports 2.0PCM - it doesn't have the bandwith for 5.1 PCM (HDMI only for that) only 2.0PCM. (PCM is uncompressed audio) However SPDIF/Toslink WILL support Dolby Digital 5.1 and DTS 5.1 as a bitstream, which your amp should then decode to 5.1.
Hence my problem. I see no menu option for selecting PCM stereo output as opposed to DTS or Dolby multi-channel audio in my sound controls for the optical output (in the 'Supported Formats' section of the 'Digital Audio S/PDIF Properties' menu. (Microsoft WMA Pro Audio is also offered in that menu, but I don't know what that is or if it changes the digital optical audio output to PCM format.) I would like to utilize the digital optical output from my PC as the DAC rep suggested if at all possible. Please advise.