Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems UHD722 Needs to Transcode Dolby Digital +

I wrote to Meridian Audio this week asking them if they could consider adding transcoding of Dolby Digital Plus (E-AC3) to normal Dolby Digital (AC3). I looked at Dolby's website and it seems like this could be possible.
The new world of Streaming boxes is all over the place with transcoding Dolby Digital +. Some do it like Amazon Fire TV and others do not like Nvidia Sheild. The Netflix App is only outputting Dolby Digital Plus as a more efficient encoding scheme for streaming. If your box does not transcode Dolby Digital Plus your out of luck getting surround sound. Dolby makes it sound like an easy transformation.

I am hoping Meridian could possibly do transcoding in the UHD722 so I sent them a request. Maybe other Meridian fans could do so too.

It doesn't have the hardware to transcode or decode. It is an audio extractor and 4k HDMI switch.

I understand the basics of audio extraction but I would be inclined to think it would be possible to extract the AC3 aspect in software from the stream especially when Dolby says "Dolby Digital Plus soundtracks are easily converted to a 640 kbps Dolby Digital signal without decoding and reencoding".

Sure it is possible to do it in software, but the hardware to do so does not exist within the UHD722.

So, in a Meridian surround setup, how does one decode audio from sources which aren’t able to decode it before it is sent out to the HD621/UHD722?

If I understand it correctly any Dolby Digital capable decoder (such as G65/G68/861 etc.) will automatically extract a Dolby Digital stream from a Dolby Digital Plus stream. Maximum number of channels is 5.1 (all this according to Dolby). I have never had an issue with this.

The UHD722 will just pass the bitstream on to the processor to do perform decoding. Having said that I couldn’t say if my sources (such as Apple TV) are performing any transcoding.

I would suspect it the source is set to output multichannel PCM to the UHD722 this unit will handle it in the same way (if it does not have DD Plus decoder).

It does not. So you are pretty much relegated to whatever the connected device can put out via PCM/LPCM.

Exactly. When running LPCM the output device will determine (sorry if I was unclear). But once again, have not had any issue with components I’ve tried not being able to do this.

Setting the output to bitstream should let the G65 etc. extract DD 5.1. Not ideal on all sources of course.

It also doesn’t make sense for it to only do transcoding. You’d want to change channel levels, delays, other types of bitstreams like DTS or Atmos. So a surround processor in the end...

I still wonder what the real story was with the HD621 and its ability to decode bitstream? Just prior to the HD621 launch, it was said on several occasions that it could do what everyone would have found useful (decode bitstream to PCM) these days, including from reliable source like Stacey Spears who no doubt would have got his information direct from Meridian as was his God like status.

Shame really, that would have been a killer feature but suspect that CODEC licensing may have had more to do with its omission than hardware capabilities. Maybe same could be said about the UHD722.