PS3 Optic Output (Linear PCM or Bitstream)

VDubFan

I was looking through my PS3 set up and noticed that there are two options for the Audio optic output. So, which one is better? Linear PCM or Bitstream. I have my PS3 hooked up to my tv via hdmi and I have a separated optic cable going to my AVR. My AVR does not process Audio through the hdmi input. It's only for switching. Thanks for any help.

cheddar

Just depends on where you want your compressed audio (Dolby Digital, DTS) decoded. You can't get lossless audio (TrueHD, DTS-HD MA, uncompressed PCM decoded in the player and passed as PCM) over the optical connection. So you're just talking about the vanilla DD and DTS available on DVDs and blu-rays.

Linear PCM is what you get after decoding. So when the player decodes the audio, it passes it to the AVR as PCM. Or, you can have it passed in undecoded form (bitstream) to the AVR where it will decode it to PCM. The only real difference is that AVRs tend to handle the LFE level more consistently if you let the AVR decode the signal. The LFE level is purposely mastered 10db lower so that it doesn't overload the connection bandwidth. If it's decoded in the AVR, the AVR always knows to bump the LFE +10db to get it back to the original level. With PCM, all the AVR knows is that it's getting a multichannel PCM signal. AVRs don't always know to bump the LFE +10db and so the AVR sometimes has to be set to bump the LFE for the PCM signal in the AVR set-up menus.

Long story short, just use bitstream as you should get the same PCM either way. You only really need Linear PCM with lossless blu-ray audio over HDMI.

adam2434

Since this regards the optical output, it should be the same context as a standard DVD player.

Choose bitstream if you want the DD or DTS to be decoded by your AVR. This is the only way to get the multi-channel surround from the optical output.

Choose PCM if you want all soundtracks to be down-mixed and sent as 2-channel PCM. You would only choose this if you did not have a full surround speaker set-up, or if you only have a 2-ch system with an outboard DAC.

VDubFan

Thanks for the help.