How does the PCM audio track compare to the Dolby Digital soundtrack?
Dolby Digital is a multi-channel format that supports up to 5.1 channels (i.e., 5 main full-frequency channels plus a low frequency effects “.1” channel). However, a 5.1-channel Dolby Digital track uses a lower data rate than a 2-channel PCM stereo signal. This is possible because Dolby Digital uses a perceptual lossly encoding scheme. This means the Dolby Digital encoder discards (hence “lossy”) some of the more difficult to hear audio signals (hence “perceptual”, based on studies of human hearing phenomena). Audio purists will probably find the PCM audio track to offer better sound quality, though only in 2-channel stereo. Casual listeners with home theater systems will probably enjoy the multi-channel experience that Dolby Digital 5.1 offers, though the audio quality may not be as good as PCM. The same comment can be made for DTS 5.1 soundtracks, since it is also another multi-channel perceptual lossy encoding algorithm.
Related Questions
- When I play a Blu-Ray disc and select the HD audio soundtrack, the display just says Dolby Digital or DTS, but does not say Dolby TrueHD or DTS HD. Why?
- What is the PCM audio track option and how does it compare to audio CDs, Dolby Digital, and DTS?
- How does the PCM audio track compare to the Dolby Digital soundtrack?