Question about the decoders in my Yamaha RX-V1600

[GlocksRock]

I've noticed that when I have my receiver set to auto detect the signal, and when I watch a movie that is DD 5.1 EX, it doesn't automatically pick up the EX, but all the flags on the receiver show up and it automatically selects Dolby Pro Logic IIx. I know I can manually put it into EX mode, but why wouldn't it know the difference between EX and PL IIx, is it something to do with the disc not being flagged correctly, or is it my receiver?

 

[MDS]

When you say all the flags on the display show up, do you mean the receiver indicates that the format is DD-EX? If so, then the disc was correctly flagged and it did pick it up.

Some receivers have options for handling ex in the menu. Usually you can set it to automatically switch to DD-EX if it detects the flag, never switch even if it detects the flag, or to always use a particular decoder (in the case of Onkyo, you can set it to 'Last Valid' which means use the decoder that was used for this format the last time it played that format).

If you have a 7.1 setup and have similar menu options, then it is probably set to something other than 'auto'. PLIIx would be used because you have 7 speakers connected and are playing a 6.1 format.

 

[GlocksRock]

Yes, the receiver shows that all speakers are playing, so I guess the disc is flagged correctly, and I do have a 7.1 setup, but if I'm playing a disc that is DTS ES Discrete 6.1 and have it set to auto it detects that just fine. But when I play something like Star Wars Ep. II for example, that is in 5.1 EX, and the receiver is set to auto, it doesn't show anything, but last night I was watching the Incredibles and when the receiver was set to auto the DD EX light didn't show up on the receiver, just the PL IIx. So I manually changed the receiver from auto to DD EX then engaged the THX processing so I could listen in THX Surround EX. But other movies like Finding Nemo are flagged correctly, and the receiver when set to auto only shows PL IIx, not EX like they really are. Is this because I have a 7.1 and not a 6.1 setup?

 

[j_garcia]

The Star Wars movies do not have flags, and likely other movies that do not switch correctly will be the same.

7 speaker setup doesn't matter because there is no 7.1 material, only 6.1. It chooses PLIIx because that would be the next "top" choice for the auto detect function. It can see the 6.1 track but no flag, so it selects PLIIx.