Dolby 5.1 or PCM 48khz ?

[G3Teg01]

I ma running my PS3 audio from a Monster THX optical cable to my sony surround sound reciever. i was reading under the PS3 settings that when using an optical cable i should set the sound to linear pcm and DEselect the Dolby Digital 5.1ch option so i did and now it runs off PCM 48khz and i was just wondering what is better do what the ps3 settings tell me to do or kp the dolby 5.1 enabled ? also it said to keep it linear pcm but alot of people on here say to change it to bitstream so i was also wondering about that too. So any help ? hints, suggestions ?

PS3 settings for Optical Audio
http://manuals.playstation.net/docum...ings.html#1470

[Big Daddy]

Originally Posted by G3Teg01

I ma running my PS3 audio from a Monster THX optical cable to my sony surround sound reciever. i was reading under the PS3 settings that when using an optical cable i should set the sound to linear pcm and DEselect the Dolby Digital 5.1ch option so i did and now it runs off PCM 48khz and i was just wondering what is better do what the ps3 settings tell me to do or kp the dolby 5.1 enabled ? also it said to keep it linear pcm but alot of people on here say to change it to bitstream so i was also wondering about that too. So any help ? hints, suggestions ?

PS3 settings for Optical Audio
http://manuals.playstation.net/docum...ings.html#1470

1. Optical (Toslink) and Digital S/PDIF cables cannot carry Dolby Digital Plus, DTS HD High Resolution Audio, LPCM, Dolby TrueHD, and DTS HD Master audio signals. You need an HDMI cable.

2. Toslink (Optical) or Coaxial S/PDIF cannot carry a 5.1 LPCM signal, so the signal will be reduced to 2 channels only. However, any version of HDMI connection can carry the LPCM signal in full quality.

3. If you are using PS3 as your disc (both Blu-Ray and standard DVD) player and your receiver does not have an HDMI connection, use an Optical cable and set the PS3's audio output to Bitstream. However, you will only get Dolby Digital or DTS Digital surround signals.

4. If you are using PS3 as your Blu-Ray player and your receiver has an HDMI connection, use an HDMI cable and set the PS3's audio output to LPCM. If you are using a standard DVD in PS3 and an HDMI connection, you can set the player’s audio output either to bitstream or LPCM.

[G3Teg01]

so why would sony say to put it as linear pcm and not bitstream ? also i se many people mentioning that pcm might give you problems and not bitstream but i havent had any problems that i know of so whats the deal ?

[musicman1999]

your optical cable will carry full quality lpcm but in 2 channel only.

bill

[Joe Cain]

Originally Posted by G3Teg01

so why would sony say to put it as linear pcm and not bitstream ?

Because the PS3 does not (can not) bitstream the HD audio codecs DTS MA or Dolby TrueHD; instead it translates them and sends a PCM signal to the receiver.

[G3Teg01]

ok now i underdstand that but i just dont understand why some people on here say to put it at bitstream anyway to prevent problems.

[callas01]

Originally Posted by G3Teg01

ok now i underdstand that but i just dont understand why some people on here say to put it at bitstream anyway to prevent problems.

Prolly cause some people may think that if the receiver isn't doing the processing something isn't right. but it is.

[Kilian]

The link above goes to the section specifically about BD/DVD Dynamic Range Control.

Enable or disable your PS3™ system's dynamic range control feature while playing BDs and DVDs that produce Dolby Digital sound. This setting is for use only when Linear PCM audio format is selected as the audio output format.

...

• When outputting audio via an optical digital cable, you must do the following to use this feature:
- For BD playback: select [Linear PCM] under (Settings) > (BD / DVD Settings) > [BD Audio Output Format (Optical Digital)].
- For DVD playback: deselect [Dolby Digital 5.1 Ch.] under (Settings) > (Sound Settings) > [Audio Output Settings] > [Digital Out (Optical)].

All the points about what S/PDIF can or cannot do, whether it can carry lossless audio etc. do not directly answer the OP's query why choose PCM over bitstream.

The simple and relevant answer would be because the PS3 can only process dynamic range control after decoding DD stream to PCM format.

[G3Teg01]

so is that why it says to deselect the Dolby Digital 5.1 ? why not just leave it enabled ?

[Kilian]

If you insist on leaving DD 5.1 enabled via optical out, it bitstreams DD and you simply won't get dynamic range control. That's fine if you don't want it in the first place: just ignore the instructions.