FullHD-TV + 4K-Projector? Resolution problem

Hi!

My OSMC-device (raspi-4) is connected to an AVR (Marantz SR7009).

The AVR has 2 HDMI-out ports.

Port 1: Full-HD-TV since years
Port 2: new 4K-projector, now added

Is there a recommended way to use, when 2 devices has different resolutions?`4k for the projector and still fullHD for the TV?

My AVR cannot convert 4k, it only has 4K passthrough, so setting 4k as default (and let the AVR downsizing for the TV) is not possible with this AVR.

In kodi system settings I cannot set 4k! 1920x1080 is the highest resolution. How can I set 4k resolution?

Is there a solution for a easy as possible usecase for me?

The raspi 4 has two HDMI-out-ports. maybe I can use the second for the 4K-resolution and use a second HDMI-IN on the AVR? But before I buy a HDMI-cable I wanna ask you.

Thanks for replies and kind regards!

Günther

I looked at the manual https://www.marantz.com/-/media/files/documentmaster/marantzna/us/sr7009-owner-manual---english.pdf

Page 196

0 If both the HDMI MONITOR1 and HDMI MONITOR2 connectors are
connected and “Resolution” is set to “Auto”, the signals are output with a
resolution that is compatible with both TVs. When “Resolution” is not set to
“Auto”, video may not be output. In this case, set a resolution that is
compatible with both TVs. (v p. 201)
You can check which resolutions are compatible with your TV in “HDMI
Monitor 1” and “HDMI Monitor 2”. (v p. 260)
0 This can be set by pressing HDMI OUT on the main unit.

Looks to be that this could be the root cause of the behaviour. Perhaps it helps, if you power off the TV while using the projector?

Some sort of HDMI splitter might help, for example:

https://www.amazon.co.uk/HDMI-Splitter-1x2-4K-60Hz/dp/B083JVPXDY/

It’s capable of passing through a 4K video signal to one output while simultaneously outputting a downscaled 1080p image to the other one. Put it downstream of the AVR.

My reading of the Marantz manual is that if you want to display the same content on both the TV and PJ at the same time there is no way it can output 2 different resolutions. @angry.sardine’s solution would be your only option. But you won’t get HDR converted to SDR for the TV.

If you want to use one display or the other but not both at once the AVR should, logically, support 4k or 1080p depending on which monitor output you select. The note on page 201 is rather confusing - why should video not be output?