BBC iPlayer and Dolby Digital surround on PC to Av-Amp...?

Gimpymoo

Gimpymoo

Gimpymoo

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So, the setup is as so..

PC> HDMI> AV-AMP> HDMI> TV

The PC is set to 5.1 speakers. All works BUT, BBC iPlayer.

When watching a film on iPlayer for example, for films which are Dolby Digital encoded, I only get stereo, even if surround decode is enabled on the av-amp.

However, if I set the PC to 2.0, the amp is then able to decode the stereo mix to surround.

Anyone know if possible to keep the PC has 5.1 and still play iPlayer with the Dolby Digital content without having to change speaker setup all the time.

Having windows in 5.1 does something funky as the amp is then unable to see the Dolby digital signal or is ignoring them but having Windows in 5.1 should not prevent anything being passed to the amp.

I hope that makes sense.

Thanks all.
 
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A small but potentially relevant point: Just because the signal is encoded as DD doesn't necessarily mean it's DD5.1

DD2.0 is equally valid. I think I might even have someone 40s and 50s B&W films that were transfered to DVD as DD1.0

Where your amp is decoding DD straight then it will play out the signal as it sees it. Some can add surround effects to a DD2.0 signal.
 
Gimpymoo said:
The PC is set to 5.1 speakers. All works BUT, BBC iPlayer.
Click to expand...
lucid said:
A small but potentially relevant point: Just because the signal is encoded as DD doesn't necessarily mean it's DD5.1

DD2.0 is equally valid. I think I might even have someone 40s and 50s B&W films that were transfered to DVD as DD1.0

Where your amp is decoding DD straight then it will play out the signal as it sees it. Some can add surround effects to a DD2.0 signal.
Click to expand...

I understand that, but I am refering to content I know IS surround in the Dolby wrapper.

What I want to know is why relating to iPlayer, windows "blocking" the dolby signal to the amp when windows set to 5.1 which is inconvenient.

When Windows is 5.1, the amp is unable to offer pseudo 5.1 but surely the same audio signal is present?
 
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I didn't realise any of the Iplayer material has 5.1 content, I have only ever seen 2.0 streams when I download (cmd line), on a windows PC;
I thought you had to have recorded the original frreview/sat stream to have that.
 
jpaul said:
I didn't realise any of the Iplayer material has 5.1 content, I have only ever seen 2.0 streams when I download (cmd line), on a windows PC;
I thought you had to have recorded the original frreview/sat stream to have that.
Click to expand...

I am refering to live streams, no on-demand.

Will try on-demand, see what happens.
 
Same thing happens with on-demand.

I can select pseudo surround from the amp and it works as expected... ONLY if Windows is in 2.0 speaker mode.

If Windows is in 5.1, the amp just outputs stereo.
 
I don't know if I can link the full post but this is part of a reply from the BBC to someone on AVForums about iplayer audio and video quality.

With regards to 5.1 audio, we do not have any plans to add that functionality in the short term. This is still quite a niche set-up in homes and does not currently justify the cost of implementing, especially as the BBC is currently under pressure to make savings.

So doesn't look like it's available

This was late November 2020
 
Thanks, but my question is why does Windows in 5.1 prevent the amp from giving pseudo 5.1?

For example, watching Frozen on iPlayer with Dolby surround on amp gives a flawless 5.1 playback, but only when Windows is in Stereo mode.
 
Gimpymoo said:
Thanks, but my question is why does Windows in 5.1 prevent the amp from giving pseudo 5.1?

For example, watching Frozen on iPlayer with Dolby surround on amp gives a flawless 5.1 playback, but only when Windows is in Stereo mode.
Click to expand...

The reason it doesn't work right is "a PC with Windows". What I mean is that there are so many layers in the set up, not just the top line stuff such as Windows settings but also drivers and even motherboard bios settings; so many places where just one incorrect setting can ruin the whole thing.

Dolby ProLogic/ProLogicII (as distinct from Dolby Digital) works because all it needs is a signal. If it's a stereo PCM signal with Dolby Surround encoded in it then the decoder has the info for the centre and surround channels. If it's just plain stereo then the PL/PLII decoder can fake-up the centre and surround channels. Depending on the amp, if it's a DD 2.0 signal then the PLII decoder (of DTS Neo decoder) can do the same trick.

Here's where things get slightly trickier. If the signal is DD 2.0, but the PC repackages to look like DD 5.1 but with nothing in the centre and surround channels, then the amp will treat it as full DD5.1, but you'll only get sound from the front left and front right channels*

* whether or not the sub runs depends on the speaker set-up. If it's a sub/sat system then the sub is filling in for the crossover point of the main channels. There is no LFE channel encoded by Dolby Surround.


@Gimpymoo , you need to have a look at the whole PC set-up starting from the bios through to the drivers and audio out settings and any Windows settings.
 
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