Monday, November 1, 2010

Kogan KGN1080P32VAA - Avoid this TV and any other with a CultraView CV119MA mainboard

The Kogan KGN1080P32VAA TV is a lemon. Avoid it, and Kogan.

Support

Before I go on, I want to note that Kogan's support were responsive, if not helpful, about these issues. They acknowledged the EDID defect, and while they won't fix it or anything else that's wrong with the TV they did credit me $40 for my trouble, showing some sign they accept their error. Kogan have been much better than, say, Belkin when it comes to supporting their products. Given that they still haven't actually fixed anything, that says scary things about the industry, doesn't it? Anyway, here's why you should avoid this product, anything else by CultraView, and possibly anything else by Kogan:

720p EDID on a 1080p panel, mainboard programmed wrong

When I bought the KGN1080P32VAA I expected (and got) a 1080p TV with cheap and nasty LCD panel; this is, after all, a $600 1080p TV. Fine, you get what you pay for, and it's still a 1080p full HD panel.

What I didn't expect was an incorrectly programmed mainboard that sends the EDID for a 720p TV rather than a 1080p TV, making the TV not "full hd" at all (and in fact worse than native 720p due to scaling) for anything that respects the EDID! What does this say about quality control and product testing? I certainly didn't expect Kogan to have no interest in issuing a firmware update to fix it, given that the TV's mainboard, by physical examination determined to be the CultraView CV119MA is still in production and supports firmware updates via USB key. CultraView don't respond to queries and don't offer their tools or firmware for download without a username and password to their vendor/partner FTP site. Kogan say:

We have tried to get a firmware upgrade for you TV however we cannot get solution for this issue.

I would still suggest you to use the VGA as you get Full HD resolution on VGA without any issue.

Alas, there's only one VGA input and associated 3.5mm audio port. I didn't buy a TV with only one (working) input. Additionally, at 1920x1080 the (analog) VGA looks ... kind of nasty. This is partly explained by the picture issue described later.

HDMI audio and overscan

The problems with HDMI don't end with the EDID, though. The CultraView CV119MA, as shipped by Kogan, turns on overscan on digital inputs when it detects a HDMI audio signal. No HDMI audio, no overscan. HDMI audio, overscan. This means you can't get decent picture quality and HDMI audio at the same time - you have to endure the image butchery of overscan and overscan compensation, or have no audio on that input. Overscan makes no sense for digital inputs, where a perfect 1:1 pixel representation is sent and there are no scan line fringes, etc, to deal with. Sadly overscan does need to be an option because some older/broken digital output devices produce images with overscan for compatibility with ancient TVs, but should never be the default, and is something you must be able to disable. It certainly shouldn't be controlled by whether or not HDMI audio is being sent!

It's possible to disable overscan by disabling HDMI audio - if your device supports this. For my media PC, that requires telling the nVidia driver to completely ignore the EDID so it doesn't detect the HDMI audio capability of the output. I had to override the EDID anyway because the TV sends a totally bogus EDID with only 1080i and 720p resolutions over HDMI. There are a couple of ways to override the EDID though - I found that overriding just the resolutions left me with an overscanned 1080p image, while overriding the whole EDID got me a 1:1 pixel sharp-ish 1080p image. The difference: HDMI audio.

The TV doesn't offer a "1:1 pixel" mode in its zoom/aspect list, nor in its menus. The only way to control overscan is via HDMI audio. I'm gobsmacked.

Vendors unwilling to fix anything

Neither Kogan nor CultraView will supply a firmware update, or the tools to create one using the vendor customisation tools CultraView offer to vendors. Neither will supply the documentation for the mainboard, which has "PC DEBUG" (JTAG?) and "PC INPUT" (DB9 serial headers? Maybe?) on it and has updatable firmware. Examination of a firmware image I found on the 'net confirms that it's capable of being reflashed via USB.

Brightness controls pixel values not backlight

The problems don't end with a misprogrammed EDID and idiotic overscanning behaviour there, though. When you change the "brightness" setting in the TV, it doesn't adjust the backlight, it scales the pixel values down toward the black end, so you lose contrast and get horrid banding. While this can be written off as a "cheap TV" problem, it's one I never even imagined might be possible.

Horizontal blur at native 1080p

Worse: Even now that I've finally achieved a non-overscanned image at the panel's native 1080p resolution, the image is still crap. By creating a few stippled and striped b&w test patterns, I was able to determine that horizontal lines are sharp and clear - so there's no vertical scaling or distortion. An array of 1-pixel wide b&w vertical lines, though, are blurred and smudged when displayed on the TV, as if they've been scaled down then up, or up then down, before display.

The test image, unscaled, appears below. If your LCD display is set to native resolution and your browser isn't scaling the image, this image should appear as a block of fine vertical lines.

... and here's a photo of what you see on the Kogan TV. The connected machine was running Linux, but I see the same problem under Windows 7's (to use Media Center) over HDMI:

Here's an image I scaled down by 5%, then back up to original size, which demonstrates a similar effect:

Imagine what this does to text, typefaces, and most kinds of pattern. Argh!

It's just too crap

Before you say "It's a TV, not a computer monitor", let me quote from Kogan's product page for their new model 32" 1080p HD TV, the 1080P-BD32:

32"/ 81cm Full HD panel (1920x1080)
Full High Definition panel ensuring crystal clear TV with Progressive Scan up to 1080P. Doubles up as an excellent computer monitor.

While that text did not appear on the product page for my TV, it shows that Kogan, like me, think that it's reasonable to use modern HDTVs as monitors. In any case, I'm using mine for a lounge room media PC, not a regular PC, and just want it to work! I don't expect amazing quality, but actually displaying the pixels I send it and doing so with working HDMI audio surely isn't too much to ask?

After hours of work and several conversations with Kogan, I finally have the TV running at its rated 1920x1080 (1080p) resolution without horribly butchering the image with overscan. Of course, to get that far I had to override the EDID and disable HDMI audio. If there's no HDMI audio signal the TV plays the 3.5mm input on all HDMI channels - but that means you have only one input for all your channels, making the HDMI combined audio/video feature spectacularly useless, and rendering the TV effectively capable of only one distinct A+V input among from the 2 HDMI and 1 VGA ports. Needless to say, this sucks.

At this point the TV is annoying me enough that I'm planning on gutting my old laptop and using its 1080p capable LVDS output to drive the TV's panel directly, bypassing the TV mainboard. That way I'll be able to see how much of this is the panel and how much is that CultraView mainboard. If the panel is OK, I'll grab a little ARM or Via Nano board with a couple of HDMI inputs and a high-res LVDS output and build that into the case as an embedded media PC, getting rid of the CultraView part entirely.

Well, I've certainly learned one thing. I won't be buying from Kogan again unless I can test the product in person with my equipment before buying. They assemble products from 3rd party parts - which I knew. They don't push issues back to those suppliers and get fixes for them, which I didn't know and didn't expect. Poor show, Kogan.

11 comments:

  1. EDID is even a problem with my ViewSonic Monitors. I'm forever editing drivers and its been years now.

    http://forums.nvidia.com/index.php?showtopic=152013&st=0&p=1010801&#entry1010801

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  2. The real issue is that there are no consequences for selling garbage products that do not work and do not follow industry standards or implement specifications correctly.

    While users/buyers/"consumers" are largely to blame because of the relentless push for lower price above all else, the sad reality is that high price products tend to be just as buggy and defective, just more expensive. They may have better parts, but you'll still have a default EDID in a panel and an awful OSD with overscan quirks. In a high-end PC motherboard you'll still get a BIOS programmed by a pack of retarded monkeys, massaged until Windows boots then kicked out the door and forgotten. And so on.

    It's one thing to want cheap gear in the sense of "I want a basic TV; I don't need super-high colour quality or fancy features, it just needs to do its job as a TV". Unfortunately, it's hard to get that without also getting a TV designed and developed by people who don't seem to know how to bang two rocks together - or don't care.

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  3. We got a Kogan FHDLEDH32VAA for Christmas - It's been pretty good as a TV, but also has issues with computers, although nowhere near as bad as this list.

    Ours reboots when it gets VGA input it isn't happy about (like too high refresh).
    And it also switches to AV1 if the VGA signal drops out briefly, such as a resolution change or when the drivers take over from the BIOS.

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  4. Hello Craig,

    Just wondering if you could explain in details what you had to do to get your image right. I am trying the same with my computer but it's all blurry with shadows, etc. I have a Nvidia graphics and the TV works fine with the PC port.


    Cheers.

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  5. Allan: I use Linux - currently Ubuntu 11.04. I have no experience with overriding the EDID on Windows, which I presume you're using since you didn't say.

    What you need to do is prevent the nVidia driver from trying to enable HDMI audio even realizing that it is available from the TV. I did this by overriding the EDID, forcing the nVidia driver to use the EDID I captured from the VGA port of the TV instead.

    I don't know how to do it on Windows, assuming that is what you're on. Search for "disable hdmi audio nVidia" or something, I guess.

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  6. Much appreciated for the above. Will not be buying a Kogan. Anyway, what is the best 22" to 24" tv to go for? I do link up my computer (1080p) via HDMI. Thank you,
    Edward.

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  7. Hi Craig, thanks for this info, I've just bought one of these http://www.kogan.com/au/buy/32-led-tv-pvr-digital-tuner/ with the same issues you describe.

    Tell me how did you disable HDMI audio as I'd like to try this to see if it fixes the overscan issue on mine? I'm also using Linux, Ubuntu 12.04

    Thanks for any help you can offer.

    Andreas

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    Replies
    1. It depends on which graphics driver you're using. I've only done it for the nVidia binary driver, where you can either capture an EDID from a non-HDMI input and use that, or you can disable HDMI audio.

      I hooked the TV up over VGA, used nvidia-settings to capture the edid using the "Acquire edid..." option, then used a Option "CustomEDID" directive in my xorg.conf to tell the nvidia driver to use that EDID for the HDMI interface instead of reading the real one off HDMI. Instead of using the VGA EDID, you can instead capture the HDMI EDID and strip the HDMI extensions from it using edid_disable_exts.

      See: http://analogbit.com/fix_nvidia_edid

      For non-nvidia drivers, try Google: "[driver] linux disable hdmi audio" or "[driver] linux override edid" .

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    2. Thank you that is a great starting point.

      I'm using an ATI graphics card but hopefully the custom EDID setting works with the ATI binary driver also. I have this morning discovered that using the open source ATI driver fixes the issue, I guess because it does not do HDMI audio, but I'd prefer to use the binary driver, so I'll see if I can get it to work.

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    3. The EDID setting for xorg.conf that I mentioned is specific to the nVidia drivers; unless ATi happen to have implemented an identical option it won't work.

      You need to either (a) get the driver to ignore HDMI audio support from the panel, (b) disable HDMI audio support in the driver entirely or (c) trick the driver into thinking the panel doesn't support HDMI audio by overriding the EDID with one that omits the HDMI audio extensions. All three approaches are driver-specific and I haven't used the ATi driver so I can't really help more. Good luck.

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  8. Late last year I purchased a Kogan KALED553DXZA 55" TV for use as a media centre display.

    For those looking for information on this panel, I can achieve a 1:1 pixel mapping from a Windows 7 machine running an AMD GPU using the following settings:

    TV: Set "Aspect" to "Full View"
    AMD Vision Engine: "My Digital Flat Panels" -> "Scaling Options" -> Drag slider to 0%

    At that point the vertical line patterns on this page appear as perfectly even straight lines. And yes, I'm using HDMI audio as well.

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