The Blu-ray Disc format provides an enhanced viewing experience and improved surround sound listening. Blu-ray Disc players offer different audio and video output settings depending on how your player is physically connected to your home theater receiver. Compare bitstream and PCM so you can get the best audio output from your Blu-ray Disc player.

For audio, if you're connecting a Blu-ray Disc player to a home theater receiver via HDMI (the recommended method), there are two main audio output settings: Bitstream and PCM (also called LPCM). In terms of sound quality, it doesn't matter whether you set the Blu-ray Disc player's HDMI audio output to PCM or Bitstream. However, here's what happens if you choose one setting over the other.

For digital optical and coaxial connections, the bitstream output option can send a standard Dolby Digital or DTS 5.1 surround sound signal to a receiver for decoding, and the PCM option only sends a two-channel signal. A digital optical or digital coaxial cable does not have the bandwidth capacity to carry a decoded, uncompressed, full surround audio signal like an HDMI connection can.

If you set the Blu-ray Disc player to output audio as PCM, the player will perform audio decoding of all Dolby or Dolby TrueHD and DTS or DTS-HD Master Audio soundtracks internally. It will then send the decoded audio signal in an uncompressed form to the home theater receiver. As a result, the home theater receiver will not perform any additional audio decoding before sending the audio through the amplifier section and speakers.