What is the LG BX?
The BX carries over all the features from last year such as support for 4K Ultra HD (3840 x 2160) with a wide colour gamut (DCI-P3/Rec.2020) and high dynamic range (HDR10, Hybrid Log-Gamma and Dolby Vision). Annoyingly, LG still refuses to support the HDR10+ dynamic metadata format, but it has added Dolby Vision IQ. This uses a light sensor built into the TV to measure the ambient light in the room and adjust the Dolby Vision dynamic tone mapping accordingly.
LG also supports Filmmaker Mode, which provides users with an easy to select mode designed to ensure the content creator's vision is delivered exactly as they intended. The mode can be engaged automatically or manually selected, depending on your preference. There are also two ISF modes for day and night and LG also supports Calman auto-calibration software.
The BX supports ThinQ AI smart features and includes built-in Amazon Alexa and Google Assistant. The WebOS smart platform also has Disney+ and Apple TV+ added this year, making it even more comprehensive in terms of video streaming services. However, there is no Freeview Play support for the 2020 models and as such there are limited terrestrial apps available with BBC iPlayer the only one available at the time of the review. LG has said they are talking to the other app providers to have them added with ITV due soon, but this may take some time to achieve and may also not happen. Keep this in mind if you buy a 2020 LG TV.
For gamers, there are two HDMI 2.1 inputs with support including VRR, ALLM, 4K/120Hz and an extremely low input lag. New this year is NVIDIA G-SYNC compatibility for a PC gaming experience free from screen tearing or other distracting visual artefacts. The BX also features the HDR Gaming Interest Group’s HGiG Mode so gamers can enjoy high-quality visuals as game creators and developers intended when playing HDR games via consoles.
In terms of the audio side of things, there's still support for Dolby Atmos, but you'll also be able to add Bluetooth speakers to use as rear channels. However, there is no support for DTS audio on the BX.
So, with the BX looking like a bargain at this moment in time, is it worth the money or are you better spending a little more on the CX model? Let’s find out.
Design, Connections and Control
The connections consist of four HDMI inputs, with LG embracing HDMI 2.1 (48Gbps) on HDMI 3 & 4. As a result, the BX can support eARC (enhanced audio return channel), VRR (variable refresh rate), ALLM (auto low latency mode), and 4K/120Hz. Other connections include a CI slot, three USB inputs, a LAN, digital audio output, an audio/headphone out and RF and satellite antennas.
As with other 2020 models, the BX has the Magic Remote control, which remains an excellent controller that allows for quick and intuitive navigation of the webOS smart platform. The zapper also allows for voice control via the built-in smart assistants, and there’s an impressive remote app.
Out of the BoxAs normal within our reviews, we measured the out of the box picture presets to find those that get as close as possible to the industry standards. The idea is that a TV must get close to these standards in at least one of its picture modes so end users can see content as it was mastered and intended to be seen. On the LG BX, that picture preset is Filmmaker Mode (FMM).
We use Calman colour calibration software, a Murideo Seven Generator and Klein K-10A meter for measurement and calibration.
Looking at the greyscale first we can see that once again Filmmaker Mode (FMM) is very accurate indeed on this sample. The tracking is very good with just a slight dip of red energy across most of the brightness scale and a slight brightening of gamma at 90% stimulus, but our DeltaE errors are around one, which is well below the visible threshold of three, meaning there are no visible errors seen in actual TV and film content viewed in FMM.
Moving to the Rec.709 colour gamut results in FMM and again we have incredibly accurate results for an out of the box picture preset. There are a few slight errors on the graph with red a little oversaturated at 75% brightness and above, along with some tiny hue errors in green, yellow and magenta, but these are not visible with actual viewing content as our DeltaE errors are also one, the same as the greyscale. Overall, the Filmmaker Mode lives up to the hype yet again and provides an accurate performance out of the box.
CalibratedThere are full calibration controls available on the LG BX along with the ability to use Calman autoCal if you have the correct equipment or hire a professional. We used both methods and found that we came up with incredibly similar results using each one.
Our greyscale results were as close to perfect as you can get on a graph, with DeltaE errors all under 0.6 and a perfect track of the grayscale from black to white. Gamma was also good with just a slight darkening at 10% stimulus and, overall, there were no visible errors seen with TV and film material.
Moving to the Rec.709 colour gamut and correction of the saturation tracking was very good with no obvious errors seen on the graph and none with actual TV and film content on screen. Our DeltaE errors came in at 0.9 overall and as such there were no issues to report at all. The LG BX can be calibrated incredibly accurately but, out of the box, it is superb for a consumer-level TV.
HDR ResultsThe LG BX is capable of displaying HDR10, HLG and Dolby Vision HDR content. As we always do within our reviews, we measured peak brightness across window sizes in the most accurate image preset (HDR Filmmaker Mode) and D65 white.
We measured a peak brightness of 504 nits at 2%, 5% and the industry-standard 10% window size. Full-field white was 116 nits and this is around what we would expect from the entry-level panel for 2020 but, as always, peak brightness is only one part of what makes up an HDR image.
The PQ EOTF tracking to ST.2084 for HDR has two different tone mapping results for 1000 and 4000 nits mastered content with the tracking above at 1000 nits sticking to the standard before hard clipping around 504 nits, which is the peak brightness.
The tracking for 4000 nit content is a little more forgiving and follows the ST.2084 track until it starts to roll off gently to the peak brightness of 504 nits. This helps preserve peak highlight detail and give a balanced look to 4000 nit content without hard clipping all the detail out of the highlights.
Colour performance to DCI-P3 within BT.2020 is also very good with nice saturation tracking to the standard at almost all the brightness points with just green and yellow failing to reach the full 100% points. It doesn’t quite reach the full 100% coverage and like all OLEDs, the colour volume is slightly lacking but, ultimately, the HDR performance of the BX is very good indeed.
We measured BT.2020 coverage at 72% XY and 76% UV with P3 measuring in at 96% XY and 98% UV.
Related: What is Filmmaker Mode?
The LG BX also features Dolby Vision IQ which was new for the 2020 TV line-up. Dolby Vision IQ retains the original metadata that the content was mastered at, but using the light sensor in the TV, can raise the image brightness while keeping colours and greyscale accurate. The result of this is that you can watch cinematic DV content in brighter living rooms with more ambient lighting, yet retain as much of the creator’s intent as possible. Unfortunately, Dolby has insisted on adding image interpolation and noise reduction as default meaning that you are not technically seeing the content as intended, but there is a workaround to this. You need to enter the AI Service menu and switch off Genre, then go back to DV IQ and you should now be able to change those items that were greyed out previously, such as TruMotion. We would like Dolby Vision IQ to be like Filmmaker Mode and have all processing disabled as default, so it fully respects the creators' intent. Surely that is what LG and Dolby want to achieve?
Related: What is Dolby Vision IQ?
Panel uniformity was very good at most higher brightness points with no obvious signs of colour shift, dirty screen effect or banding. We did find that the panel uniformity at 5% has a few small visible bands towards the centre of the panel and darkening to the edges, but these were never visible when viewing normal film and TV content.
TruMotion has Black Frame Insertion (BFI) and is now usable in Min or Mid settings without introducing obvious flickering. High will give you obvious flicker and is best avoided. If you decide to use BFI Min or Mid you should be aware that image brightness is lowered and some light interpolation is being added, even with Blur and Judder set to off within the Motion Pro menu. BFI is not recommended for use with HDR due to the brightness drop.
Motion with 24fps content was presented properly with 5:5 pulldown with TruMotion switched off. There was no sign of any induced judder within slow pans or other movements of the camera. The α7 Gen3 AI-enhanced processor offers decent video processing and upscaling performance, but this is the weak point when comparing to the CX which offers cleaner upscaling of content with a little more detail and fewer artefacts.
In terms of gaming performance, the BX is well featured for future gaming with VRR (variable refresh rate), ALLM (auto low latency mode) and in the Dynamic Tone Mapping sub-menu is an HGiG (HDR Gaming Interest Group) setting in the Game mode. Input lag measurements using our Murideo Seven Generator in 1080/2160p 60Hz were 13ms (inc HDR) and at 1080/120 (inc HDR) at 6ms, which is identical to CX models we have previously reviewed. OLED has matured into an excellent technology for advanced gaming from consoles or PC and the issue of image retention shouldn’t be an issue as long as you avoid bright static images being on screen for a long period of time and always put the TV in standby to allow the mitigation process to take place periodically.
We did notice a few issues with just above black flickering within some low bitrate content and blacks can look pixelated and noisy with some content. This was most noticeable with SDR content from poor source material, but we also had issues with flickering in a well-used Dolby Vision scene from Stranger Things with Eleven walking through the dark, water-flooded Upside Down. However, I didn’t notice any other issues with just above blacks during the testing period, so it was only an issue with certain content types.
SDR and HDR performance is very good indeed with incredibly accurate looking images out of the box in Filmmaker Mode. As you would expect, black levels are superb with good shadow detail retrieval thanks to the per-pixel advantage of OLED. Colours also look natural and accurate with skin tones looking correct and lifelike and there is nuance to colours across the range. Films look cinematic with no obvious issues. HDR content is also superb with the same strengths added to very good peak brightness performance and colours looking well saturated but accurate and natural. Dolby Vision is also very good with no obvious issues within the image with solid blacks and strong well-saturated colours and very good APL brightness thanks to the dynamic metadata approach.
Moving to calibrated settings also didn’t change the superb performance, as after all, out of the box is incredibly impressive to start with. Calibration just adds the assurance of absolutely no visible errors at all. We found AutoCal and manual approaches to calibration worked to provide the same end results.
Sound quality is also decent on the BX with the 40W total system projecting a good enough soundstage and quality that watching normal every day TV is fine. Bass is pretty non-existent and film soundtracks do feel they are missing the weight and immersion you'd expect, but for watching the news, game shows and sports, the built-in speakers do a decent job. Obviously, they can easily be bettered by using a soundbar or other off-board sound system.
WebOS 5.0 smart TV is present on the BX and works as expected, but I did find the interface to be a little more sluggish than the GX I have been using for a few months. This was also true with the UI in general, but I doubt you would notice this in isolation. All the major apps are available minus the Freeview Play line-up from last year, but in terms of the terrestrial apps, they are slowly starting to appear one by one on the LG 2020 models with iPlayer available and ITV due soon. That aside, the OS is excellent and still the best available on the market.
- Filmmaker mode accuracy out of the box
- HDMI 2.1 (48Gbps) x 2
- Excellent gaming features
- Excellent SDR image quality
- Very good HDR image quality
- Dolby Vision (IQ) & Dolby Atmos
- WebOS 5.0 smart TV
- Excellent value for money
- Some black flicker with certain content
- Slight lag with UI and Smart TV
- No DTS audio
- No Freeview Play and some UK terrestrial apps still missing
LG BX 4K OLED TV Review
I had the BX side by side with a GX model in my testing room. The GX and CX use the same panels and processor with very similar picture quality results, they however have a different design. In isolation and for anyone who is not a pixel peeper and constantly assessing image quality, the BX looks very similar in everyday use to the GX in terms of picture quality. Where things start to change is with critical movie viewing and in side-by-side tests, the GX has better colour reproduction and just above black performance. Menu and UI speed is also faster on the GX along with 4 HDMI 2.1 inputs. In every other respect, there is not much else that separates them in terms of features or performance.
Ultimately, it will come down to if you need more than 2 HDMI 2.1 inputs and the slightly better dark room viewing advantages in just above black performance and slightly nicer looking colour reproduction, against the few hundred pounds difference in price between the BX and CX.
The LG BX certainly builds on last year’s models, adding some useful new features and is close in picture quality and features to the higher models in the 2020 line-up. The BX remains a great choice for those looking for an entry-level OLED TV with bags of useful features, an accurate image out of the box and two HDMI 2.1 ports for the latest gaming tech. At just under £1000 for the 55-inch at the time of this review in March 2021, the BX comes Recommended.
Contrast/Dynamic Range/Black Level
SDR Picture Quality
HDR Picture Quality
Picture Quality Out-of-the-Box
Picture Quality Calibrated
Ease of Use
Value for Money
Our Review Ethos
To comment on what you've read here, click the Discussion tab and post a reply.