HDMI 2.1, eARC & LG DTS - how does it work

[Five_Star]

My AV setup is ancient and so a full upgrade is needed for the xbox series x and PS5.

Thinking of the LG GX with a Denon AVR-X3600H amp.

I'm really confused about how to make everything play nicely with HDMI 2.1 in the right places, how eARC actually works in practice, and how I can still support DTS audio from the PC?

The LG has 4x HDMI 2.1 ports, however, I am used to plugging devices into the amp, then passing that into the TV via a single HDMI cable. (mostly as my old TV has limited ports)

From reading this is not suggested now? To take advantage of the TV features external devices plug in directly?

Audio is then sent to the amp via eARC - how is this setup, is it automatic, is it set and forget?

It seems that AV amps with multiple HDMI 2.1 ports are not yet available, or will even be available if the preferred route is TV connection rather than amp -> TV?

The other issue is DTS audio. The LG no longer supports it, so if I plug my PC into the LG CX will it pass-through DTS audio to the Denon, is eARC capable of this?
OR
Will I have to use the single HDMI 2.1 in on the Denon for the PC, decode the DTS on the amp then send the picture up to the TV
OR
Do I need to plug the PC into the TV HDMI port and sepertaly output via Optical to the amp?

Reviews for both the LG CX/GX and the newer HDMI 2.1 amps maddeningly gloss over the implementation details for these details only mentioning the official specs!

 

[Radox-0]

I have a C9 rather then CX and use a Sony STR-1080 which supports eARC. C9 and CX are similar though aside from DTS support in that both support same formats and with firmware updates for C9 earlier in the year, multchannel PCM.

For myself I plug all my devices into the C9 directly and AV receiver via eARC port. benefit of this is full HDMI 2.1 for upcoming GPU's but for now allows the G-Sync to work fine (which most AV receivers on market will not pass through). On the TV i set eARC as passthrough and it feeds the audio signal right through to the AV receiver perfectly. AV receiver can play all audio formats fine without any intervention from any devices connected to the TV. In fact my AV receiver is now hidden away and not been touched for months. Turns on and off with TV and everything controlled via TV remote. The PC can similarly with multichannel PCM address each speaker fine also.

However as you mentioned, the CX does not support DTS and it will not passthrough DTS audio signals. I gather plenty of CX owners get away with it by not living with DTS and seem to do okay as there are usually other formats available for most the part with it seeing little use. Consoles can output PCM format fine as can PC's and plenty of streaming services do not use DTS.

If you really want DTS for whatever reason but VRR (G-Sync / Freesync) and higher refresh rate 4k, then likely need to look at an audio splitter device people mention (forget the name right now), or get one of those HDMI 2.1 receivers coming out as you mentioned.

 

[Daaaavvveee]

If your tv does not have eARC you can buy an Fury Arcana Unit which splits the signal so you can get Atmos sound through an Atmos Soundbar for example.
I have just ordered one, around £150.

Not sure if I can link it here, but search Google for "4k Arcana 18Gbps".

 

[Five_Star]

Helpful replies, thanks.

Good point about G-Sync not being passed through, I hadn't thought of that! I guess with eARC this is unlikely to change in the future as AV amps will be less about supporting extended picture standards and more on processing return audio signals.

That's very interesting that eARC can mean having the amp unit located in a more remote location to give a cleaner viewing setup, an unexpected benefit!

DTS - I guess it's the decline to a dead format, phased out in blu ray and streaming sites it seems. I really need to have a close look at what media I have with only DTS audio. I suspect a lot has been re-issued in blu ray now or 4k blu ray or available direct from a streaming service. I just know there will be an annoying couple of releases that will need to be ripped and converted longer term.

 

[lucid]

DTS - I guess it's the decline to a dead format, phased out in blu ray and streaming sites it seems.

Not quite an accurate assessment, there.

For DVD, DTS was very much the minority format. The tables turned with Blu-ray though. DTS-HD Master Audio was (and remains) the dominant format, though there's not the massive difference in #1st and #2nd as there is with DVD.

The positions reversed again with overhead surround as seen mostly with 4K UHD BD. Dolby were first out of the gates with ATMOS, so it got a lead over DTS:X which was defined later.

When it comes to broadcast and streaming, space is at a premium. For this reason the broadcasters couldn't use a lossless base-system such as DD True-HD or DTS-HD MA. They opted instead for a lossy system; this is how we've got Dolby Digital Plus.

For someone who only ever streams via the net then it would appear that DTS isn't a big deal. That's understandable. However, for those with Blu-rays, DTS is very much the prime format.

 

[Five_Star]

Not quite an accurate assessment, there.

I'm happy to be corrected

With all that you said then, have LG dropped support only for 'classic' DTS? The question then becomes is DTS-HD MA or DTS:X still available and passes through the CX /GX panels to amp or soundbar?

I've got loads and loads of DVDs, only a couple of blu ray discs that I'd still like to support, but just now with single HDMI 2.1 connections for AV amps it might well be worth waiting a little longer that battling a workaround.

 

[Radox-0]

I'm happy to be corrected

With all that you said then, have LG dropped support only for 'classic' DTS? The question then becomes is DTS-HD MA or DTS:X still available and passes through the CX /GX panels to amp or soundbar?

I've got loads and loads of DVDs, only a couple of blu ray discs that I'd still like to support, but just now with single HDMI 2.1 connections for AV amps it might well be worth waiting a little longer that battling a workaround.

In those instances, could you not just plug a blu-ray player directly into the AV receiver directly, but for everything else via the TV you want to leverage VRR / 4K @ higher resolution on the consoles / PC? I mean your not worried about the HDMI 2.1 element of things so it should be a non-issue? Would mean you do not need to get rid of your AV receiver which does list eARC support.

 

[Five_Star]

Yes, you are right. It's easy to become fixated on things and while the very newest AV amps have a single HDMI 2.1 port, there are plenty of devices like blu-ray players that do not require it to fill the other 6-7 HDMI ports thanks to the xbox, ps5 and pc taking up the ones on the actual TV.