Originally Posted by NorthSky
I see; it works for the HDMI Audio Out too...LPCM down-mixed to 7.1 channels. >>> I am going to try that too, and see if it sounds as good or even better than Dolby Pro Logic IIx.
Ok, time for me to backtrack. I just went down to my theater to verify that I had set my multichannel speaker setup to 7.1 downmix and found it set to 5.1 - and my rears were silent. So much for my theory.
I found that the only way to get surround sound from the rears on 5.1 material is inside my AVR, as you had said. It's a Yamaha Aventage RX-A1030 (two models back - which I just got new from Amazon, almost half price because of that fact).
Go to Sound Program, Surround Decode, press the up arrow to configure it, and while on the line for surround decoder press the Options button on the remote. This brings up a new menu, one of the entries being Extended Surround. Click on that and change it from Off to PLIIx Movie. This applies to all inputs.
Then, to keep pressing the Blu-ray Scene shortcut button from defeating that, go to that Scene, press up to configure it, and then click Save. Once you've saved it, it won't defeat the surround decoding.
Now, even in Bitstream, putting in a 5.1 or 7.1 disk will give you sound out of the rears, and it automatically shifts between the two modes.
I may have heard slightly better sound from Bitstream than from LPCM in switching back and forth, but there were so many steps in between. and there's expectation bias, so I'm not sure.
It makes sense to me to leave the audio in its original format as long as possible, so I'm now leaving the Oppo set to Bitstream except when and if a disk has authoring problems, in which case I'll switch to LPCM output.