Question about LPCM and Dolby TrueHD

J

jbost002

Audioholic Intern
OK, so I have my new Onkyo TX-SR605 receiver and BA speakers and sub and I have a question:

I am using my PS3 for Blu-Ray playback and I am trying to get Dolby TrueHD to work. I think it's working, but I am not for sure. What setting should I have the "Surround Mode" on the receiver set to? The manual is no help...I currently have it set to DVD Direct.

My PS3 is outputting in Linear PCM. Is this the right setting? I have cycled through the "Surround Modes" and have no option for Dolby TrueHD.

Also, when I'm watching Sattelite, should it be set to CBL Direct to automatically detect the correct decoder for whatever I'm watching?

Thanks for the help! You guys have been a BIG help already!
 
avaserfi

avaserfi

Audioholic Ninja
Since the PS3 will not pass Dolby TrueHD via bitstream it is still required that the PS3 do the processing. So leave it on the LPCM output setting. This will send the already decoded TrueHD information from the PS3 to your Onkyo then straight to your speakers.

When you turn a BD on go to audio options and select Dolby TrueHD. After that you are good and will be listening in full HD.

The surround modes sound like DSPs to me. I would just let them be and tell the Onkyo to accept the LPCM signal and do nothing to it except maybe PLIIx if you have a seven channel set up.
 
M

MDS

Audioholic Spartan
Decoders like DD, DTS, True HD, etc are not surround modes that you can select. When the bitstream is identified as being that format and you have the digital input format set to Auto, it will automatically choose that decoder.

Since the receiver is getting PCM the only surround modes you should be able to choose are PLII(x), Neo:6, and the 'Onkyo original DSP'.
 
J

jbost002

Audioholic Intern
Great! I think that makes sense...now to figure out how to do the auto function on the Onkyo...I guess maybe that's the DVD Direct/CBL Direct? That's what it sounds like...awesome!
 
M

MDS

Audioholic Spartan
There is a button on the front of the receiver labled 'digital input'. If you press and hold it for 3 seconds the display will change and show the input format. It should be Auto by default so you won't likely need to change it.

By the way, you can press the Display button to show the format of the incoming signal. In this case it should say PCM 48 kHz (or whatever it is).
 
B

bass addict

Junior Audioholic
The surround modes sound like DSPs to me. I would just let them be and tell the Onkyo to accept the LPCM signal and do nothing to it except maybe PLIIx if you have a seven channel set up.
I'm pretty sure the 605 is not capable of laying PLIIx over a PCM signal. You have to upgrade to the 805 or higher to take advantage of this.

Since the receiver is getting PCM the only surround modes you should be able to choose are PLII(x), Neo:6, and the 'Onkyo original DSP'.
Most of your newer receivers are capable of processing a PCM signal. I can apply PLIIx or THX modes to a PCM signal with my 875.
 
M

MDS

Audioholic Spartan
I'm confused bass_addict. Your two statements contradict each other.

ALL receivers can use PLII (5.1) or PLIIx (7.1) on a 2 channel PCM signal.

I don't have any multi-channel PCM sources like this topic where a player converts Dolby True HD into multi-channel PCM so I can't say definitively that a receiver could use PLII(x) on such a signal, but the Onkyo manual shows that it can. The chart in the manual is the same as it has always been, just updated to now show the new formats it can decode and it does list PLII when the PCM input is 32-96 kHz.
 
B

bass addict

Junior Audioholic
I'm confused bass_addict. Your two statements contradict each other.

ALL receivers can use PLII (5.1) or PLIIx (7.1) on a 2 channel PCM signal.

I don't have any multi-channel PCM sources like this topic where a player converts Dolby True HD into multi-channel PCM so I can't say definitively that a receiver could use PLII(x) on such a signal, but the Onkyo manual shows that it can. The chart in the manual is the same as it has always been, just updated to now show the new formats it can decode and it does list PLII when the PCM input is 32-96 kHz.

Sorry, I'm at work and was rapidly reading through the question. To clarify. Most all receivers can take a DD5.1 or PCM 2 channel signal and post process it, overlaying PLIIx, THX, etc. What the 605 is not capable of is taking a MCPCM signal via HDMI and post processing it to 7.1.
 
J

jbost002

Audioholic Intern
So what you are saying is that my receiver won't convert the LPCM from the PS3 TrueHD and make it do 7.1?
 
M

MDS

Audioholic Spartan
So what you are saying is that my receiver won't convert the LPCM from the PS3 TrueHD and make it do 7.1?
Yes, that is what he is saying. If the receiver gets 5.1 multi-channel PCM it cannot process that into 7.1 using the ProLogic IIx decoder.

When you press the Display button on the receiver, what does it show for the incoming signal format?
 
avaserfi

avaserfi

Audioholic Ninja
Yes, that is what he is saying. If the receiver gets 5.1 multi-channel PCM it cannot process that into 7.1 using the ProLogic IIx decoder.

When you press the Display button on the receiver, what does it show for the incoming signal format?
I think that depends on the receiver. I know my Denon 3806 can take a multi-channel (6 channel or less) PCM signal from my PS3 and apply PLIIx so I get a seven channel signal. The receiver says "Multi-Channel+PLIIx" and everything works great.
 
B

bass addict

Junior Audioholic
I think that depends on the receiver. I know my Denon 3806 can take a multi-channel (6 channel or less) PCM signal from my PS3 and apply PLIIx so I get a seven channel signal. The receiver says "Multi-Channel+PLIIx" and everything works great.
Yes, which is what I stated earlier. My 875 and my old Pioneer 84 could apply processing to a MCPCM signal. The receiver he is implying about cannot. That is one of the complaints and subsequent reason most people stepped up to the 805 instead.
 

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