Joe Schmoe

If DTS-HD MA and Dolby TrueHD are digital and the PS3 outputs hi def audio via HDMI (a digital connection), then why/how does it output these signals as PCM? Is PCM analog? Why not just output them as DTS-HD MA and Dolby TrueHD?

X

PCM (Pulse-Code Modulation) is digital. Many people say it is a waste of space.

Here's more about it:

http://www.hemagazine.com/node/Dolby...compressed_PCM

Nick Martin

Is this another one of those "I don't see my little display logo light up" complaints? It's hard to tell with these things.

Joe Schmoe

I guess it is. Your average consumer is not going to know that PCM = Dolby TrueHD or DTS-HD MA. Hell, I didn't even know that PCM is digital. I searched the Home Theater FAQ section before I posted this but saw nothing about the PS3.

By the way, why not make it easy on the clueless and have the receiver display the same thing the player says it's outputing? What a concept! God forbid electronic manufacturers make the transition from DVD surround sound to Hi Def surround sound easy for the general public.

Joe Schmoe

Thanks for the link.

Nick Martin

In your case you don't know that it doesn't cut down on the quality to have it output as PCM, but for most who complain about not seeing that "TrueHD" or "DTS HD-MA" logo light up on their receivers, they are fully aware that it's still the same quality but complain only because they just want to see those logos light up.

Joe Schmoe

Those little logos serve as confirmation and save people from having to seek out confirmation elsewhere (like in this forum or from a clerk at Best Buy). But it's good to know it's the same quality.

It begs the question though: why not just output the audio as Dolby TrueHD or DTS-HD MA and eliminate any confusion for consumers?

shaun3000

It's a limitation of the PS3 hardware. From what I've read, it is physically unable to bitstream a lossless codec. But it has more than enough processing power to decode the codecs internally and output them as LPCM. When the PS3 first came out, it didn't even support all the HD audio codecs but they were added via software updates.

Joe Schmoe

Thanks!

Spiky

It is more complicated to decode to PCM than to bitstream. And LPCM takes more bandwidth than Dolby or DTS. The PS3 did it this way for greater compatibility with processors (and HDMI versions) of the time, not because they couldn't manage bitstreaming.

shaun3000

Correct. But the chips they chose to use and continue to use are incapable of bitstreaming those codecs.

CaptStormy

Please pardon this question. If I have my PS3 Hooked to my Onkyo 607. Setting it up to PCM is better then setting it to Bitstream? Personally I do not mind if my Logos do not light up. Thanks in advance.

SoSpacey

PCM is your only choice since the PS3 does not bitstream 5 channel audio.

CaptStormy

What is it transmitting then? All speakers are presently working at Bitstream. OK...Will change it tonight!

CaptStormy

ANd i am hooked up as 7.1

BSTNFAN

I have the PS3 and an Onkyo 606...I use PCM so that I can have the new HD codecs (DTS-MA and Dolby TrueHD). The PS3 cannot bitstream these and will instead send the lossy "regular" versions. Bitstream will light up the nice logo lights and will still sound very good, but will be slightly inferior when DTS-MA or Dolby TrueHD are options. The Onkyo can still use Dolby PL IIx or other similar processing to turn non-7.1 into 7.1 if you desire.

SoSpacey

Dolby PL IIx actually adds 2 additional front channels, similar to Yamaha Presence. It's goofy and 98% of america will never use it.

Josh Z

ProLogic IIx adds 2 center rear channels, not 2 front channels. Anyone with a 7.1 audio configuration no doubt uses ProLogic IIx.

You may be confusing this with ProLogic IIz, which adds 2 height channels to the front, rather than the 2 surround back channels.

Spiky

Your receiver should tell you, what does it say?

Nick Martin

I had to connect my surround channel speakers to my surround back speaker ports of my receiver, because I found I was missing certain sounds when watching a 7.1 disc since I have a 5.1 setup. Now I get what I was missing before and still get the correct surround output from a conventional 5.1 mix. An odd solution but an effective one.

Spiky

There may be a setting in the receiver menu where you can choose whether the "surround" or "back surround" outputs for 5.1 output. And yours is set to the back set. Or it's just the only way it works.

Nick Martin

What happened was I bought the CSI season 1 Blu-ray which has 7.1 surround audio. I know the mix of the opening theme (Who Are You) inside and out and I was missing those bouncing synthesizer effects that sort of zig-zag from the left and right surround channels. When I couldn't hear them, as well as realizing that what I was hearing behind me wasn't nearly as discrete I plugged in a couple of additional speakers into the surround back ports and gave a listen.

Turns out those discrete sounds were moved to the surround back channels, along with all the discrete surround activity one would typically hear in the rears of a 5.1 mix. Deselecting the 7.1 output options on the PS3 didn't help - the rear surrounds were simply ignored. Turning off surround back decoding on the receiver did nothing as well, so I just moved the speaker connections into the surround backs, and that was that - 5.1 is the same as always and I get the correct output of the 7.1 rears. The 7.1 mix of CSI as well as the Star Trek Blu-ray releases was unnecessary, since the sounds output in those surround channels aren't really discrete. There's nothing exclusive to them. It's basically Pro-Logic IIx done for the listener in advance.

K&AJones

I wanted some clarification on the different codecs (True-HD, etc..) being passed thru only certain outputs. I'm from old school of the straight out D.D5.1 and DTS and not all these other ones. We just had to worry about digital inputs such as having enough optical and coax.

Correct me if I wrong on this but to get the current codecs like True-HD and DTS_HD I need a HDMI connection? Both of our current receivers don't have the HDMI connections, only optical and coax. The one I would pair the PS3 to has DD, DTS, DD-EX, DTS 96/24 and DTS-ES. I'm trying to get a idea if the PS3 is limited based on outputs and internal prcessing vesus some of the newer stand-alone units.


Kenny J

shaun3000

S/PDIF, both optical and digital, does not have enough bandwidth to carry an "HD" lossless audio signal. At most, it can carry two channels. (Stereo) The three choices for BD are DTS-MA, DD-TrueHD, and LPCM. (LPCM is uncompressed, the other two are compressed but lossless, kind of like a ZIP file)

Many players, including the PS3, are capable of decoding the new codecs internally and outputting as LPCM. (That's the ONLY option with the PS3) If you have a stand-alone player, many of them have analog multichannel outputs, so that is an option to get lossless sound. If you want to keep it digital, you will need an HDMI cable and a receiver capable of at least accepting a multi-channel LPCM signal.

If you don't want to upgrade your receiver, just pick one of the DD or DTS soundtracks. Your player will output regular DD or DTS via S/PDIF to your receiver. Depending on the player, some may re-compress multichannel LPCM as DD, others just pass a stereo signal. The BD spec requires either regular DD or DTS to be present on the disc. DD-TrueHD will include a separate DD track for the player to output. DTS-MA is backwards-compatible with regular DTS, but you only get the lossy signal. Even though they are lossy signals, BD has so much space that they always max-out the bitrates on the lossy codecs. So the DD or DTS track on BD will generally sound better than DVD. (Think of DVD sound as 128k MP3 and DD sound as 320k MP3)

Spiky

What he said.

Also:
If you are considering adding a different player, but not a new receiver, tell us if your receivers have a 5.1 analog input.

If you are considering a new receiver, any current models with HDMI should be fine with the PS3. You would need to check if they can play 5.1 channel PCM 96/24, but I think they all do.