Yamaha RX-V563 7.1, rear speakers no sound during blu-ray playback

When playing a Blu-ray movie (have tried Enemy of the State, Deja Vu, We were Soldiers) using any of the 5.1 audio options available on the disc, I get very weak output from the surround left and right speakers and nil output from the rear left and right speakers. This is when using any of the main Yamaha "sound fields".

All speakers are functional as I can get moderate sound (moderate relative to the front 3 speakers) from all 4 of the surround speakers if I use the 7ch Stereo or 7ch Enhancer mode but I believe these modes are limited and for a different purpose.

I have tried lifting the speaker level for the surrounds and while this has some improvement, it only works on the left and right, not the rear ones and feels like I am forcing the issue unnecessarily.

Best sound quality I have achieved so far is when I play a music DVD, swith the PS3 HDMI audio setting to "Bitstream" and then using the "Sur. Decode" option to decode the 2 channel source to PLIIx Music or Neo:6 Music. I seem to get a nice strong output through all speakers; not flat like the 7ch Stereo and 7ch Enhancer modes.

Equipment is as follows...
Receiver – Yamaha RXV563 (part of YHT-795 7.1 channel theatre package)
Blu-ray player – PS3 80gb
Display – Pioneer LX508
HDMI connection – PS3 to receiver and receiver to TV

Why would anyone contemplate a 7.1 system if the rear spkrs are unused for almost all Blu-ray movies? Surely I should be able to get surround sound across the 1st 5 spkrs, then some sort of matrixed sound from the rear? Someone please tell me if I am expecting too much from my system.

Re: Yamaha RX-V563 7.1, rear speakers no sound during blu-ray playback

How do you have the PS3 connected? Assuming you are using HDMI you should be able to listen to Dolby True HD and DTS MA through your system. The PS3 needs to be set up to output LPCM over HDMI and you simply need to press the straight effect button on your yamaha remote or front panel. Your RX-V563 can accept LPCM up to 7.1 I believe. The front panel of the yamaha will say PCM or MPCM and you should see 5 to 7 speaker icons depending on the movie. There is also also a sur decode button which you can press that may allow you to matrix the additional two channels in the event the movie is only 5.1 as most are (although I am not sure if it will work with this level of Yamaha).

Mark

Re: Yamaha RX-V563 7.1, rear speakers no sound during blu-ray playback

As Mark said, only TrueHD and DTS-HD offer discrete 7.1 tracks, of which there are currently not very many titles available. For possibly the first time in home theater evolution, we have more capable codecs available for home use than theatrically. Theatrical mixes are still mostly limited to 5.1, with some presentations in 6.1 (Dolby EX), which is a mono back channel intentionally matrixed into the surround left/right channels. To create a 7.1 mix for Blu-ray, the entire movie has to be remixed instead of just being encoded from the original 5.1 theatrical master.

Most home 7.1 is done, just as you said, by matrixing the back two channels of 5.1 into 7.1 using DPLIIx or Neo:6. The amount of signal present in the SB channels will depend on how the side surround channels were mixed. With DPLIIx, the closer to identical the SL/SR are, the less signal will be derived for the SBL/SBR channels since DPL flavors use phase differences to derive the matrix. Neo:6 uses frequency differences to derive the matrix, which can generate more activity, but can also sound gimmicky at times, IMO. Neither is really trying to create an rear image that calls attention to itself, just trying to create an image that is more solid from side to side. It's something that you'll notice as different or even missing if you turn the matrix mode off, collapsing to 5.1, but not necessarily feel you can point to it when engaged.

The 563 can matrix regular DD and DTS, but given its price point in the Yamaha lineup, it may not have the processing power to matrix MPCM (it wouldn't be the first)...check your manual, there should be a chart explaining what modes can be applied to what type of signal.

-Brent