Originally Posted by Vampidemic
DTS-MA = lossless compression
PCM = uncompressed
DTS-MA and TrueHD are used in favor of PCM on media because they reduce the amount of space needed to store the soundtrack on the disc without any loss in audio quality, allowing producers to use that space for higher quality video and/or more content.
When you set your player to send Multi channel PCM, your player decodes the compressed audio and sends the uncompressed bits to your AVR. With bitstream, the AVR decodes the compressed signal encoded on the disc and plays back the uncompressed bits. So in either case it should be the same bits getting sent to your speakers.
Found this on Wikipedia:
DTS-HD Master Audio may be transported to AV receivers in 5.1, 6.1 or 7.1 channels, at lossless quality, in one of three ways depending on player and/or receiver support:
Over 6, 7 or 8 RCA connectors as analog audio, using the player's internal decoder and digital-to-analog converter (DAC).
Over HDMI 1.1 (or higher) connections as 6-, 7- or 8-channel linear PCM, using the player's decoder and the AV receiver's DAC.
Over HDMI 1.3 (or higher) connections as the original DTS-HD Master Audio bitstream, with decoding and DAC both done by the AV receiver.
The last paragraph is interesting. Does this mean I need a 1.3 hdmi cable for proper decoding by the avr when the bd sends as primary pass through? I currently have 1.2a cables.