General EDID issues and how to identify them

Note: Pulse-Eight Neo Matrices do not offer video format downscaling.

Note: Many Pulse-Eight Neo Matrices are not capable of downmixing Dolby Audio, please refer to your matrix's specification sheet to see what is supported by your matrix.

This article is intended to show how to view the supported EDIDs from your Neo Matrix WebUI and understand issues that can occur due to using unsupported EDIDs

"EDID data exchange is a standardized means for a display to communicate its capabilities to a source device. The premise of this communications is for the display to relay its operational characteristics, such as its native resolution, to the attached source, and then allow the source to generate the necessary video characteristics to match the needs of the display. This maximizes the functional compatibility between devices without requiring a user to configure them manually, thus reducing the potential for incorrect settings and adjustments that could compromise the quality of the displayed images and overall reliability of the system."

When using a Neo Range Matrix, the matrix will request the relevant EDID data from both the Output and Source Device, this is used to ask the output device what formats of video and audio it can support and to ask the source what formats of video and audio it can provide. To check these you need to open your WebUI and login to the admin area (for more information on how to do this please see the matrix user manual)

From the Video Routing Tab you will have two columns, they are headed Inputs and Outputs. To see the EDID of an individual device locate that device in the list, In the same column on the right hand side of the row will be either a symbol that looks like an AV Rack or a Monitorclicking these will present you with more options.

Input Side

On the Output side when clicking the AV Rack symbol  we will get the a window load similar to the one presented below.

On the Input side you will see:

• RED The EDID profile, in this example we are requesting Ultra HD (4k), this can be changed to a different EDID profile for a number of potential reasons including but not limited to reducing bandwidth for longer transmission, ensuring that all the TVs are able to accept this EDID if this is not done automatically, changing the Audio EDID for the use of a surround sound system.
• BLUE The Video Signal that is currently being received from this input device. In this example we are receiving 2160p or 4K UHD, this means that any TV unable to display 4K would not be able to produce an image using this Input's Current Video Signal.
• YELLOW By clicking where it says EDID Details in Green you will get another page showing the Advanced EDID Information

Here we can see a variety of information about the EDID. Although all the information on this page can be extremely useful the following points are ones that are most likely to have an affect on your overall system.

Colour Formats and Max Video Quality

This will tell you the available colour sampling and chroma settings that can be transmitted. This can be important as the video matrix may have a maximum video resolution that will affect your refresh rate. For example the Neo4 matrix supports 4K@60Hz 4:2:0 or 4K@30Hz 4:4:4. This means that if you are only able to send 4:4:4 you will only be able to achieve 30Hz at 4K. If you are able to send 4:2:0 colour you can increase the monitor refresh rate to 60Hz.

Video Modes (HDR)

If your input device supports HDR this is where it will list the speed in Hz in which the HDR is sent. Different Neo Range Matrices have different requirements on what HDR they can process. For example the Neo 4 can support HDR10@24Hz whereas the Neo X+ can support HDR10@60Hz. If the HDR is not sent within spec it is common to see visual anomalies such as issues with colour hue or even no picture.

Supported Resolutions

This is the most common section we will check when looking for EDID issues on a Neo Matrix. In this list are all the resolutions that the Input Device supports. In this instance we are able to distribute 4K in a variety of different ratios. If however we only saw the highest EDID at 1080p we would be unable to get a 4K signal from this device. When we review the output side it is important to observe this section in relation to the output to ensure that the video formats we are requesting are supported at the output device.

Speakers 

This will display if the input device is capable of sending audio for surround sound systems, stereo speakers, mono speakers or other audio arrangements. in this example we can see it supports L+R speakers

Audio Codecs

Here we can see the audio formats that the input device supports, in this case it can only support 2 channel PCM however if you are looking to run a surround sound system you would need to support 5.1 or 7.1 audio. Please note the capabilities of your matrix if you are planning to break out any of the audio via the audio output ports if available. Many of our matrices do not support Dolby Downmixing however we can pass through Dolby Audio via HDBaseT.

Output Side

On the Output side when clicking the monitor symbol we will get a similar window to the Input Side but with several key differences

Here we can see:

• RED the length of the cable, this is important as different matrix and receiver combinations can support different ranges at 1080p and at 4K. If you are trying to transmit 4K on a Neo X:SR or using a Neo Lite Receiver above 40m you are unlikely to receive video signal in a readable state on the output.
• BLUE the Video Signal Currently being sent to this output, this is important when we go to the Advanced EDID Information for this output as it will need to match the supported resolutions to have video working correctly.
• YELLOW By clicking where it says EDID Details you will get another page showing the Advanced EDID Information

The layout here is the same as on the input side, however now this is the EDID settings for the TV connected

Similar to on the input side we need to observe the:

Colour Formats and Max Video Quality

Now that we have already looked at the colour formats and max video quality on the input side in the examples given we can compare that they share the same maximum video quality. This means that if paired with a matrix that can support the video quality then we can get the best quality and colour out of our input and the output device.

Video Modes (HDR)

Here we can see that this output device supports SDR (Standard Dynamic Range), SMTP and HLG (Hybrid Logic Gamma) HDR modes.

Our input device cannot support any of these and no HDR should be passed through however even if they did share SMTP or HLG these are not supported by our Matrices. Please check your matrix's specification sheet to see what HDR can be supported by your matrix.

Supported Resolutions

In this example the Samsung TV is able to accept most of the same EDID profiles as the input can support. At 1080p or 4K we should not have any issue, however if your output device does not support the resolution it is receiving as seen on the output menu then you will only see a black screen. In this instance request a lower EDID profile from the input device or adjust the settings on the device itself to a supported resolution and then check that the video format being received is one that is supported. Please note that on many smart devices it is possible to force 4K on the device settings and our EDID Profile will not be able to override this as we do not downscale any of the information we receive from the source device.

It is also again important to keep in mind transmission distances at 1080p and 4K of your matrix and receivers.

Speakers

Here we can see that the TV is fitted with the standard L+R stereo speakers which is supported by the input

Audio Codecs

Here we can see that again this TV supports 2 channel PCM which is the same as the input.

If all of these settings match and are supported by the Neo Matrix you should not have any EDID related issues affecting the image on your screen and the audio from your output device via HDMI.

FAQs

I am seeing video on my screen but I am not getting audio

If you are getting the video through but none of the audio is coming through please review that the audio format outputting from the input device is a format that can be read by the output device. When using HDBaseT video and audio are encrypted together and are not treated as separate streams. They are encrypted, sent and decrypted so that they come out in the same way that they are received. Therefore the matrix will not lose audio and keep video. This scenario would indicate that the audio format is not recognisable by the output device.

I have a strange colour hue to the image on my output device

Assuming that the output device is working correctly and not experiencing a technical problem of its own this image is likely caused by HDR being enabled on the input device. If the HDR is not supported then colours can be compressed incorrectly and although you still have image the colour will be incorrect.

I have no image but I have audio

This should not be possible, counter intuitively from the paragraph about getting video and no audio to put things in an overly simplified way the video frames contain much more data than the audio and when sent together from the input device the audio is put in around the video information. If this were an EDID related problem then you would expect to lose both audio and video. Your issue is not with your EDID settings.