4K content with amp

Kemik

Kemik

Kemik

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Joined
7 Nov 2005
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Widnes
Hi guys,

I bought an LG 55B7V a few days ago and set it up yesterday. Previous TV was a 1080p 3D so I have never had a 4K TV before. Input all goes via an Onkyo HTX-22HDX before passing to the TV. As far as I am aware, the HDMI cables used are all 1.4.

Went to watch Virgin Media this morning to find it having weird sound and video issues. If I have the TV off, the sound works great. If I restart Virgin Media, I see the start up and then it screws up. I switched HDMI cables, same thing. I put the HDMI direct to the TV and it worked great.

Then I fixed it, I switched Virgin Media from auto detect (4K) down to 1080p and everything worked. Is the bottleneck likely to be the HDMI cable or the amp?

Thanks!
 
The problem is unlikely to be the cables unless they're over 5m in length. High Speed rated HDMI cables have enough bandwidth capacity for basic 4K/UHD.

For a proper idea of system compatibility you need to be looking at the capabilities of the HDMI sockets on the gear rather than the cables connecting to them. The Onkyo has HDMI 1.4 rated sockets as you've said. That's enough for basic UHD such as scaling up 1080p to UHD resolution, but it's not designed to be compatible with High Dynamic Range (HDR).

To make matters slightly more complicated, there also the issue of EDID (Extended Display Identification Data). This is the list of feature compatibilities carried by each device. You'll have seen EDID at work when you've switched sources and noticed it takes a while for the system to fart around before you get a picture. That's all the devices talking to each other to establish a common set of compatibilities.

AFAIK, although the latest gen' VM boxes have a 4K/UHD mode there's very little (if any) UHD content in UHD apart from BT Sport. At this stage then, it's pointless setting the VM box for 4K/UHD output unless you have a BT Sport subscription watch it a lot. The TV will do a better job of scaling 1080p to UHD than the VM box. Set the VM box to 1080p and let the TV do any scaling required. I know that's a bit frustrating because you want to experience the benefits of the new telly, but unless the signal is properly UHD/4K at source then it's not getting a full resolution signal.

An alternative way forward is to take Optical audio from the VM box and keep the direct HDMI connection to the TV. This will bypass the bottleneck of the Onkyo system but there are a few caveats to watch out for. The main one is the loss of HDMI control. Optical is just a connection for audio signal. There's no control function down it. You'll have to change volume using the Onkyo remote.
 
I've changed the settings, which fixed it until I moved some HDMI ports around to try and setup ARC for Chromecast. Unfortunately it is now still showing grey bars. As soon as you turn the TV off the sound comes through the amp perfectly fine, so I still think it is a bandwidth issue somewhere. The amp is going crazy trying to work out the profile from the VM box (display shows the audio type, etc when its working fine).

Might have to do as suggested for a work around - video direct to TV then audio out to amp. That isn't too much of an issue as I have a Harmony remote.

Arc also wouldn't work, but that's more down to the fact that the amp hides the ARC channel when not in use so Harmony can't track the channel properly.
 
The system doesn't support 4k video, that's why the sound works when the screen is off.

From the manual:

• 3 HDMI*1 inputs, 1 output (HDMI Version 1.4, with 3D Over HDMI and Audio Return Chan￾nel, plus support for up to 1080p, Deep Color, x.v.Color, Lip Sync, DTS-HD Master Audio*2,
DTS-HD High Resolution Audio, Dolby TrueHD*3, Dolby Digital Plus, SACD, and multi￾channel PCM)
Click to expand...
 
You could always forgoe ARC and just use the amp's optical connection from the TV.

You may also find that the latest V6 box requires HDCP 2.2 compliance, which your amp doesn't support over it's HDMI ports.
 
My AV amp can only do 4k 30hz and doesn't have HDCP 2.2. I just use a 4k 60hz splitter box with HDCP 2.2 and coaxial/optical audio extraction instead. I run coax digital cable from that to AV amp and it works well.

All my sources like Fire tv 4k, computer etc go via HDMI to that little box then box has one lead going to 4k tv.
 
(maybe i picked up wrong end of stick)
With the recent thread about new virgin media boxes with their hdcp2.2/hdmi2.0 failing to negotiate a connection with 1080p tv hdcp2.0/hdmi1.4,
so virgin were obliged to provide hdcp strippers (or give a waiver on a months fee) ,
if you tell them you have this problem,
can the stripper then be used between the vm box and the amp, so that 4k material can pass through amp, it would not pass hdr material which needs
hdcp2.2, but there aren't any such programmes anyway ?

as lucid said you want to let tv do its probably better scaling and feed it 1080p if the source is that
(i say probably because the mpeg noise reduction on the vm box may combine that with scaling ... so it could be better)

nlyh said:
I just use a 4k 60hz splitter box
Click to expand...
is this too, a stripper
 
barmyllama said:
You may also find that the latest V6 box requires HDCP 2.2 compliance, which your amp doesn't support over it's HDMI ports.
Click to expand...

It worked before I switched TV's :(

nlyh said:
My AV amp can only do 4k 30hz and doesn't have HDCP 2.2. I just use a 4k 60hz splitter box with HDCP 2.2 and coaxial/optical audio extraction instead. I run coax digital cable from that to AV amp and it works well.

All my sources like Fire tv 4k, computer etc go via HDMI to that little box then box has one lead going to 4k tv.
Click to expand...

Will give it a go, but that's kind of the point of the amp and harmony :(
 
On the splitter suggestion, will I need a separate splitter for each 4k source? E.g. if I wanted to use my PS4 too I can either limit the PS4 to 1080p or put it via a splitter? Beginning to feel like an upgraded AVR is required at some point when I start using the PS4 again...
 
Kemik, I know this is an old-ish thread but did you ever get this sorted? I have the same amp and would be interested if you tried the splitter box or just upgraded your kit.
 
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