Issue with Dolby Digital from blu-ray player

[rawpowerocks]

I was wondering if anybody may be able to help me.

My setup is a Sony blu-ray player, which is connected to my Sony TV via hdmi. I also have a Sonos Beam soundbar connected to the TV via hdmi arc.

When I play a blu-ray disc movie which has DTS audio I get no audio through the Sonos Beam because it is not compatible with DTS. The Sonos Beam reports the audio in is DTS and it is not supported. That is exactly what I was expecting, so no surprises for me there.

This is what my issue/problem is....

The blu-ray player has audio settings. One of those settings is 'Dolby D Compatible Output' which I then turn on. This setting says it converts DTS audio to Dolby Digital for output. But even after turning this setting on my Sonos Beam still reports the audio in is DTS not Dolby Digital, which seems weird to me as it should report Dolby Digital. Am because its receiving DTS I still have no audio.

The only way I seem to get audio through the Sonos Beam is by putting the blu-ray player 'Digital Audio Output' setting to PCM rather than auto. Then I can actually hear the movie. But the Sonos Beam then reports that the audio in is Stereo 2.0.

Why can't I get Dolby Digital from my blu-ray player to the Sonos Beam? Any ideas to what my problem is? Am I missing a setting somewhere that I need to adjust? 

Any help/advice would be greatly appreciated as its driving me nuts

[rawpowerocks]

TV = KD-55XE8596 according to the manual it is arc (not earc) and the arc port is compatible with Dobly Digital & Dolby Digital Plus 

Blu-ray player (main) = BDP-S6700

Blu-ray player (secondary) = BDP-S3500

If I change the audio setting within the blu-ray disc audio settings and select a Dolby audio it all works as it should and Dolby is being sent by both blu-ray players and Dolby is being received by anything that is connected to them. So the problem isn't with the TV or the HDMI arc ports. That shows Dolby can be sent between both blu-ray players and TV via the HDMI arc port. So the problem must be with the DTS to Dolby conversion option on the players. This doesn't seem to be working. But I don't understand why Sony would include that option/setting/feature on the blu-ray players if they are not capable of converting DTS to Dolby?

[williamfsmith]

I am happy to be proved wrong but I doubt the ability to convert DTS HD to Dolby Digital in real time. They are two completely separate formats

I suspect the option is there so that the Blu-ray player successfully decodes Dolby Digital when you select the Dolby Digital soundtrack on the Blu-Ray.

I have an AV Receiver so I let the Receiver decode the audio stream rather than the Blu-Ray player. In your case I believe you rely on the Blu-Ray player to decode the sound and pass it to your TV which is linked to the non DTS capable Soundbar.

So to hear Dolby Digital 5.1 from a soundbar you need to select that audio track when you play a Blu-ray

Incidentally, whilst my receiver can decode both if its present on the disc the Blu-ray always defaults to DTS-HD

Selecting PCM is by default only ever going to get you stereo. 

[rawpowerocks]

this is what the blu-ray players manual says about it

'Dolby D Compatible Output' -

[On] Converts DTS audio source to Dolby Digital Audio by using EDID (Extended Display Identification Data)

[Off] Turns off the function

If I put this option off and select a Dobly audio setting from the disc, Dolby is still sent and received. So it would appear this option has nothing to do with the blu-ray players ability to get the Dolby from this disc.

I want Dolby as I want to turn the audio dynamic range (compressor) on. I have this option on the blu-ray players and the TV. But this option only works on Dolby audio sources. Which is why I thought the convert setting would be the answer. But the convert setting doesn't actually seem to do anything. Or at least anything I can work out

[williamfsmith]

Perhaps this thread will clarify/help

Seems PCM can be capable of more than stereo given the right environment.

Sonos Forum seems to be a great place to research identical issues.

[merseyswine]

Like used to be so simple. Now you need a ****ing PhD just to watch telly

[royabrown2]

@rawpowerocks 

If this paragraph is to be believed:-

If you combine the bitstream and secondary audio settings, the Blu-ray Disc player will down-res surround formats, such as Dolby TrueHD or DTS-HD, to standard Dolby Digital or DTS to squeeze both types of audio signals into the same bitstream bandwidth. In this case, the home theater receiver recognizes the signal as standard Dolby Digital and decodes appropriately.

from https://www.lifewire.com/blu-ray-audio-bitstream-vs-pcm-1846396

then it looks as if the key is having secondary audio on.

So try:-

Digital Audio Output [Auto]

BD Audio MIX Setting [On]

Dolby D Compatible Output [On]

Downmix [Surround]

where we might hope that MIX On would trigger the downres, and DDCO would convert what was downrezzed to Dolby D instead of DTS, and send it onward as bitstream for the Sonos to process further.

My BDP-S6700 is upstairs on the Orbitsound bar (only 2.1) so I can’t speak for surround, but on Optical, the DDCO On setting on the 6700 means the only surround option offered by the TV is Dolby Digital, with DTS greyed out. And this plays the DTS-HD Master Audio soundtrack of my Sopranos box set just fine, albeit only 2.1

But if I turn DDCO Off, then the TV offers me DTS, and Dolby Digital is greyed out. But if I choose that DTS, then I just get ear-splitting white (grey?) noise.

So:

(i) the setting of DDCO is working and making a difference 

and

(ii) be very glad your Sonos at least recognises DTS and mutes it.

[royabrown2]

@merseyswine 

Bummer. I’ll just have to struggle along with my Master’s 👨🏻‍🎓

[merseyswine]

Christ Almighty- even Doc Emmett Brown’s back-to-the-future DeLorean time machine can’t have been this complicated!

[merseyswine]

Well then I have no chance at all with my mere Batchelor of Engineering (1971, would you believe. I might as well go back to our old 1955 9-inch monochrome Bush TV in the walnut cabinet. It just had 4 knobs: channel select (BBC or ITV), volume, brightness and on/off. The channel select ***** was an after-market addition when ITV appeared. A man came to the house and drilled a hole in the cabinet and installed a tuning capacitor and the *****. He had a little paint brush and a tiny pot of white paint which he used to paint the letters ITV and BBC in neat little white letters. I was 5 at the time and it was at my Grandad’s house. 

[royabrown2]

@merseyswine 

Whirligig, Watch with Mother, Muffin the Mule, Andy Pandy, Bill and Ben....

Aah, they really knew how to make television then.

And comics - how to write comics. My TTOM is still one of my proudest achievements.....