Transporting Multichannel Sound to an Audio Receiver
If analog connections are used to pipe audio from the PC to the receiver, the PC must decode the Dolby or DTS encoded data first, then convert it from digital into analog signals, which are then transmitted across 3 (5.1) or 4 (7.1) cables to the receiver for amplification and delivery to the loudspeakers. These cables are generally designated as center plus LFE (two channels), right and left front, right and left rear surround, and right and left surround (7.1 only).
Part 1 Conclusion: If LPCM Won’t work, You’re Stuck with Dolby Digital or DTS
In Part 2, we’ll examine the hardware and software components on a PC that are involved in handling high-definition audio bitstreams from a Blu-ray disc. Unless you’ve got some really, really new hardware, you probably won’t be able to use HDMI 1.3a to transport these formats natively. But if your PC can manage to decode one of those formats into LPCM, or your Blu-ray disc includes an LPCM audio track, and you deliver that LPCM stream via HDMI to your receiver or preamp/preprocessor, you’ll be in pretty good shape. Otherwise, the only way to get multichannel (5.1 or better) audio from your PC to your receiver requires you to decode digital audio into its analog equivalent in your machine, and then to use 3 (5.1) or 4 (7.1) analog audio cables to ferry that audio into your receiver or preamp/preprocessor. Much, much more on that in Part 2!