topic Betreff: KD48A9 Dolby Vision /HDMI 2.1? in Android TV

KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 04:15:22 GMT

Hi there,

Two questions, number one. How do i access Dolby Vision? It says from retailers this tv has it but i can't locate it anywhere. There's no option in the picture mode settings and no option under video signal HDMI settings. All i get is HDR10 and HLG, no option for Dolby Vision. Unless you have to be on a certain programme for it to pop up, i can't find it.

Second question. Sonys own specs for this TV list "feature earc for HDMI2.1" does this mean its third HDMI port is infact a 2.1 or am i being mislead?

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Peter_S. — Mon, 28 Sep 2020 07:15:29 GMT

Hi Josh,

Yes your TV does support Dolpy Vision if you playback such content. You cannot turn on DV for standard content manually.

eARC is available for HDMI 3 only, that's correct. However, HDMI 2.1 is available for all the HDMI connectors.

Cheers

Peter

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 10:15:27 GMT

Hi Peter thanks for the reply and answering both questions.

I'm not willing to doubt you but are you sure all ports support HDMI 2.1. In the manual it states the number for using the enhanced support feature and the number 18gpbs which is HDMI 2.0. If you look at the Hz and the resolution for the TV it will only go up to 60hz unless its in 1080p which can transfer up to 120hz which is also an indication of HDMI 2.0. The confusing part for me is as i stated in the Sony UK specs on its it own website it did state "Specifications for HDMI 2.1 eARC" it doesn't tell you the specs of the other ports to be exact and it doesn't state whether that specification is used in a port on the TV which is 2.1 or if it has borrowed that one feature from the software of a 2.1.

I hope you're right, because it would help me decide to not return the TV. Its the bandwidth i need for certain features to be used when the PS5 is out. And so far when you go to some retailers it'll state it had 4 HDMI 2.0b, 2.0a 2.0 or one 2.1 port. It's honestly a mess of information, something i didn't fully research before i bought the product, my fault.

I know you've clarifed all ports are 2.1, is there anyway you could be wrong? If you aren't is there any source to clarify with?

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

rooobb — Mon, 28 Sep 2020 10:34:33 GMT

AFAIK only the Sony model XH90 and ZH8 have some ports HDMI 2.1 with full bandwidth as of now. I'm sure Peter will clarify better.

If you'll need full bandwidth 4k 120fps HDR RGB on the new consoles is an another matter...

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 10:56:26 GMT

I'll have to wait for further clarification. Its all very confusing my tv either has one port HDMI 2.1 specified in sony online specs relating to a feature. It has all ports HDMI 2.1 or no ports and only holds one feature currently eARC which can be compatible with a 2.0b port. I was under the impression you cannot upgrade ports with a software update. However also in the specs it states all ports have HDCP2.3 which are found in HDMI 2.1 RTX support. So has Sony developed technology to software upgrade these ports in the future? I don't know, i need more clarification. It is very confusing to say the least.

The 4k full RGB with 120fps isn't a necessity for me personally. What is will be the 4K HDR10 (RGB) at 60 fps. Something the HDMI 2.0 won't do with out Chroma sub sampling to 4:2:2. I don't wish to lose that depth of colour on a 2 grand television.

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

rooobb — Mon, 28 Sep 2020 10:52:45 GMT

HDMI 2.1 is confusing by definition, since any manufacturer can decide which features implement of the whole set declaring that is HDMI 2.1. eARC is an HDMI 2.1 even if it can be implemented without changing the bandwidth of the port. Even LG that claims to have all 4 ports full featured HDMI 2.1 this year decided to allow only 40gbps instead of the 48gbps of the standard. But they are still 2.1.

You have to carefully look for the specification you really need and look for them. An enlarged bandwidth requires a dedicated controller that cannot be implement by software.

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 11:10:07 GMT

I understand that but you can't claim HDMI 2.1 with 18 gpbs with no other features other than eARC on an individual port. This is why i need clarification from Peter or anyone else.

I've been through the testing standards as to what makes a port HDMI 2.1 if whst you're telling me is correct it means no ports support HDMI 2.1.

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

rooobb — Mon, 28 Sep 2020 11:29:43 GMT

I'm not stating nothing that is not official. You have to specifically claim which HDMI 2.1 the product is supporting an this is what Sony claims https://www.sony.co.uk/electronics/televisions/a8-series/specifications

FEATURES SPECIFIED IN HDMI2.1:

eARC

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 13:16:58 GMT

But there is no bandwith increase in that port? It doesn't clarify this either for me. Only when looking at the owners manual are you able to distinguish that the other ports hold 18gpbs. This is a rough selling point for people like myself who atleast thought i could run the option of 4k @60hz with HDR10 at 4:4:4. You'd only need a bandwith of 24 gpbs to do that.

A question for you then Rob, if I'm unable to achieve that on this TV and can only run it at a maximum of 4k 60hz HDR10 sub sampling at 4:2:2, will there be noticeable difference in colour compression?

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

rooobb — Mon, 28 Sep 2020 13:26:14 GMT

As you said for full RGB color 10 bit depth 4k@60hz HDMI 2.0 is not enough. There are some people also in this community that reports that the eARC port (even if still a 2.0b one) does allow for it, but it out of specs and I would not rely on it. Now, I'm not a gamer nor I use the TV as a PC monitor but looking at what you can find in the internet not using 4:4:4 you may have some issue in the rendering of text (even if I don't see any use of a pc monitor in 4k60fps HDR 4:4:4 either if not while gaming). Movies are already using 4:2:0 subsampling in the mastering so no use on them

PS: btw AFAIK eARC is implemented using the ethernet channel of the ultra high speed cable to enhance the return channel bandwidth, so it doesn't need any additional bandwidth on the other side of the communication channel

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Peter_S. — Mon, 28 Sep 2020 13:40:01 GMT

Hi Josh,

I have to apologize - I mixed up the specifications of the models..

A9 does support eARC only from HDMI 2.1 specs but nothing else.

Please also check below information:

		HDMI 2.1 features
Type	Model	eARC	4K120	VRR	ALLM
8K LCD	ZH8	YES	YES*	NO	NO
8K LCD	ZG9	YES	YES*	NO	NO
4K OLED	A9S	YES	NO	NO	NO
4K OLED	A8	YES	NO	NO	NO
4K LCD	XH95	YES	NO	NO	NO
	XH90/92	YES	YES*	YES*	YES*
	XH85/91	YES	NO	NO	NO
	XH80/81	NO	NO	NO	NO

* Software update needed

Again, apologies for the confusion.

Cheers

Peter

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 13:44:53 GMT

I'm not exactly versed in knowing a lot about this stuff. Are you saying that the eARC input doesn't rely on the current bandwith the other ports have? Does that mean it will take upless bandwidth than the others if you were running the tv at a higher spec when plugged into something like a PlayStation 5 at the other end? Or am i just making that up in my head 😂.

You'll have to describe it a bit better for me to understand, sorry.

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 13:46:48 GMT

Thanks Peter for the update.

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

rooobb — Mon, 28 Sep 2020 13:57:08 GMT

@Josh009 ha scritto:

I'm not exactly versed in knowing a lot about this stuff. Are you saying that the eARC input doesn't rely on the current bandwith the other ports have? Does that mean it will take upless bandwidth than the others if you were running the tv at a higher spec when plugged into something like a PlayStation 5 at the other end? Or am i just making that up in my head 😂.

You'll have to describe it a bit better for me to understand, sorry.

ARC/eARC are return channels features (ARC means literally Audio Return Channel), they send signal from the TV back to the compatible device (an audio device only).

Video signal go through an HDMI connection the opposite way (FROM the device to the TV)

The bandwidth allocated to each flow of the connection is not shared, so you cannot use less of ARC/eARC channel and more for the video signal. Nonetheless it seems that the port labeled as ARC/eARC on Sony tv may have more than the standard 18gbps on the video channel. But this is only speculation being that there is no statement from Sony on this.

Is it more clear?

Thanks @Peter_S. for the clarification, i missed up things as well referring to A8 specification, but they are exactly the same of the A9

Betreff: KD48A9 Dolby Vision /HDMI 2.1?

Josh009 — Mon, 28 Sep 2020 14:46:04 GMT

Yes that clears things up for me, thank you very much. I do hope Sony could clarify if this Hdmi 2.1 input has more than 18gpbs bandwidth and it isn't just for the feature of eARC. I can't see it located anywhere in the manual stipulating otherwise.

Well atleast this has informed me of my options. All i wanted was to run this tv with 60hz4k with HDR10. I've since read about Chroma sub sampling with video games in particular and it seems to make very little to no difference from 4:4 4 to the lower 4:2:2, 4:2:0, unless you're using it as a PC monitor. Still the extra bandwith wouldn't go a miss. I'm completely uninterested in 120hz, it's not something i would ever notice if it's not present.

Anyway thank you again for your help, hopefully others will take advice from this to.