LG 55B7 4K OLED TV Review
It's got the lot
What is the LG B7?The B7 might technically be LG's entry-level OLED 4K TV for 2017 but a quick look at its feature list and you realise that it's nothing of the sort. LG have publicly stated that all their 2017 OLED Ultra HD TVs use the same panel and system-on-chip (SoC) which means there should be no difference in picture quality. All their 2017 OLED TVs also support every version of HDR, use WebOS 3.5 and even support Dolby Atmos. So basically the five models in this year's LG OLED range are actually differentiated by cosmetic features and sound quality rather than picture quality, which raises an interesting question.
Is there any point buying the more expensive W7, G7 or E7 models when you can pick up the C7 or B7 for less and still get the same picture quality? In this review we'll find out by testing the B7 and comparing it directly to the OLED65E7 that we were reviewing at the same time. The OLED55B7 has a suggested price of £2,999, as at the time of writing (June 2017), which is very tempting when you consider all the formats it supports and the included features. There's also the option of the OLED55C7 which costs the same but has a different stand and is a Currys exclusive, although in all other respects it appears to be identical. So let's see if the B7 is the bargain that it appears to be on paper.
This review was based on a retail sample of the LG OLED55B7 kindly provided by Richer Sounds. Please support our reviews by considering Richer Sounds for your next TV purchase.
DesignIn terms of the B7's design, LG have kept things simple with an ultra-slim – or Blade Slim as LG refer to it – OLED panel that has a 10mm wide black border around the screen and a chrome trim around the outer edge. That's it as far as the front goes and we really like this clean minimalist approach. At the top the panel of the B7 is only 4mm deep but this widens out to 49mm about half way down. It's here that the electronics, speakers, amplification and connections are all housed and there are also air vents at the top of this section. The rear is as minimalist but as stylish as the front, with the top half finished in a silver brushed metal effect and the bottom composed of white plastic.The B7 sits on a very attractive curved chrome stand that connects to the rear of the panel and gives the impression that the B7 is floating in mid-air. The stand can't be swivelled but is solid and stable, complimenting the rest of the TV very nicely. There is 70mm of clearance beneath the screen when using the stand, so bear that in mind if you're considering a soundbar. You'll need a surface that is at least 740 x 254mm on which to place the B7, although you can also wall mount it and there are 300x200 VESA brackets for that purpose. Overall the 55" B7 measures 1229 x 764 x 254mm (WxHxD) including the stand and weighs in at 18.6kg and, whilst it isn't quite as classy or well made as the more expensive E7, it's still a solid and attractive TV.
The B7 uses a minimalist design that is both simple and attractive
Connections & ControlIn terms of its connections the B7 certainly isn't found wanting, with a combination of sideways and rearwards facing inputs. They are all at the bottom left as you face the screen, although annoyingly the sideways facing connections are only 100mm from the edge of the screen which might make hiding cables tricky. The sideways connections are composed of two HDMI inputs, two USB ports (3.0 and 2.0) and a CI (Common Interface) slot. Facing rearwards you’ll find two more HDMI inputs, another USB 2.0 port, an Ethernet port (although there is also built-in WiFi), terrestrial and satellite tuners, an optical digital output, a headphone socket and an RS232 connector for serial control. All the HDMI inputs support 4K/60p, High Dynamic Range (HDR10, HLG and Dolby Vision), Rec. 2020 and HDCP 2.2, whilst one of them also supports ARC (Audio Return Channel).The B7 comes with the same plain glossy black Magic remote that was included with the B6 and C6 last year and it remains a bit of a fingerprint magnet. Whilst not quite as nice as the controller included with the E7, this remains an excellent remote that has been ergonomically designed to fit very comfortably in your hand. As a result controlling the user interface on the TV is a seamless experience and all the key buttons that you’ll need, including navigation controls and a track wheel, are in within easy reach of your thumb. The remote includes a pointer function that is highly effective and perfectly compliments the WebOS smart TV platform. As with the E7 controller, LG have dropped the 3D button and moved the Settings button in order to add direct access keys for Netflix and Amazon Prime. Although this is an excellent remote, some people may prefer to use their smart device as a controller and if so there is also an effective free remote app for iOS and Android.
There's a full compliment of connections, along with the excellent Magic remote control
Features & SpecsAs we mentioned in the introduction, the B7 might technically be the entry level model of LG's OLED range this year but there's nothing entry-level about the features included. All of LG's OLED TVs this year use the same panel and system-on-chip (SoC), so whichever one you choose you'll get a flat 4K Ultra HD 10-bit panel with a refresh rate of 120Hz and support for wider colour gamuts and all four versions of High Dynamic Range – HDR10, Dolby Vision, Hybrid Log-Gamma (HLG) and even Advanced HDR by Technicolor. LG's OLED TVs are also all Ultra HD Premium certified by the UHD Alliance and, as part of their partnership with Dolby, they support Atmos. As with all of LG's models this year the B7 does not support 3D but every TV manufacturer has now dropped this particular failed format.
MORE: What is Dolby Vision?
WebOS 3.5 is the latest version of LG's excellent smart TV system and essentially remains the same, delivering a responsive, robust and intuitive platform that treats everything as an app and can be effectively navigated using the Magic Remote. The latest version adds some new features, including the OLED Gallery which allows you to choose Art Frame, Rainy Window, Sunny Day or your own photos to appear on the screen.
This year LG have also included an option called Zoom Record which allows you to record a zoomed section of the image and there's also the option to use the Music Player in full screen mode with lyric synchronisation, if you fancy a bit of karaoke. Finally LG have added the ability to enjoy 360 degree material on your TV screen and use the Magic Remote to drag the pointer and look around the 360 degree environment.
As with previous generations of WebOS there's the LG Content Store, a full web browser, all the main video streaming services such as Amazon, Netflix, Now TV, YouTube, Wuaki TV and a complete set of TV catch-up services. It's a testament to how effective the WebOS platform was from the very start that, even in its latest iteration, it remains essentially the same aside from a few tweaks.
Considering the price the B7 is feature-packed with support for all versions of HDR
Picture Settings – Out-of-the-BoxAs usual we used the ISF Expert (Dark Room) and (Bright Room) modes which provide the most accurate measurements against the industry standards and bypass the sharpness controls. If you’re tempted to use the HDR Effect mode we recommend you don’t because SDR content is graded to be seen that way and never intended to look like HDR, so you’ll just end up with blown-out highlights and over-saturated colours.
The basic setup of the B7 is essentially the same as last year but there have been some minor changes made to the menus and controls. LG have now renamed the Normal Colour Gamut as Auto, which better explains what it actually does. You should always leave the Colour Gamut in Auto as it will automatically detect and select the correct colour gamut. The default setting for brightness is still 50 but there the control is far more granular around that point, allowing better fine tuning of shadow detail just above black.
All our measurements were done with a Klein K-10A colour meter, a Murideo Fresco Six-G pattern generator and CalMAN Ultimate calibration software. You can find our suggested settings here or alternatively you can follow the simple steps in our PicturePerfect Guide.As you can see from the graph above, the out-of-the-box greyscale was reasonable, although there was a deficit of red compared to green and blue across most of the scale. As a result there was a slight push towards cyan, which is composed of green and blue, but any errors were only on the threshold of being visible. The gamma could have been better and was tracking around 2.3 rather than our target of 2.4 but at least shadow detail wasn't being crushed just above black. We were able to leave the Brightness control at 50 and still be able to see detail just above black, which wasn't possible last year.LG have made improvements to the colour performance of this year’s OLED TVs, using a larger 3D LUT (Look Up Table) with 17x17x17 or 4,913 points. Previous OLED generations had used a 9X9X9 3D LUT with 729 points, so the TV has six times the accuracy. In terms of the colour processing, LG initially apply a 1D LUT and then use the 3D LUT for hue correction, which they feel delivers superior colour gamut mapping with HDR. The colour accuracy was certainly very good, aside from some slight hue errors in green and magenta. The Auto colour gamut was working effectively and the increased accuracy of the new 3D LUTs certainly delivered accurate tracking across all the saturation points.
Although comparing the graphs between the E7 and B7 do point to some very minute differences, in actual fact these will not be visible, even when placed side by side given the low deltaE errors. This points to both sets being very accurate out of the box and highlights that there are no hand picked golden samples sent to reviewers. We give LG credit for producing such accurate out-of-the-box settings, although some professional calibrators may not feel the same way.
The out-of-the-box performance was excellent and near-reference after calibration
Picture Settings – CalibratedAs usual for an LG TV the B7 includes both a 2-point and a 20-point white balance control, which means we should be able to get a near-perfect greyscale and gamma performance. There is also a Colour Management System (CMS) but, by LG's own admission, this is flawed and introduces artefacts into the image, so this is best avoided. However if the tracking remains as good as the out-of-the-box performance, then once we’ve calibrated the greyscale this shouldn’t be an issue.
As we suspected we were able to get a very accurate greyscale by using the 2-point white balance control and we then simply fine tuned both the greyscale and gamma with the 20-point to get a near perfect performance with all the DeltaE (errors) well below one. Both the B7 and E7 were identical after calibration.After calibrating the greyscale the slight cyan push was gone and the colour temperature of white was now hitting its target of D65 (6500K) precisely. As a result the colour performance was now excellent and the tracking was equally impressive. The luminance levels (which are not shown on the graph above) were spot-on and although there were some slight hue errors in magenta, red was a little over-saturated in places and blue a little under-saturated, overall this is a great performance that proves you don't really need the CMS to deliver accurate colours.
Picture Settings – HDRCompared to last year the HDR picture modes have been expanded and renamed, so the most accurate mode is Cinema, although there is also Cinema Home which increases the luminance and colour temperature for brighter environments. We would always recommend selecting the Cinema mode for both HDR10 and Dolby Vision content. With HDR10 or HLG content the new LG OLEDs default to Dynamic Contrast on Low, which is the Active HDR setting. Switching to Mid or High doesn’t make any difference but we found that this setting would clip detail, so we recommend turning it off. Aside from that you can leave the majority of the settings at their default positions, although this year LG have added a two-point white balance control in the HDR mode.In terms of the HDR performance the B7 was impressive with an accurate greyscale that measured with equal amounts of red, green and blue. The performance against the PQ EOTF was also very good, with the OLED tracking it closely aside from a slight sag towards the lower part of the curve. We actually measured the peak brightness of the B7 at 680nits using a 10% window and we could get nearer 700nits with a 1% window, which means that those peak or specular highlights can appear quite bright. In addition, since an OLED works at a pixel level the highlights can also be delivered with exacting precision. The B7 delivered around 320nits on a 50% screen and over 130nits on a 100% screen due to the ABL (Automatic Brightness Limiter) kicking but this is an improvement on last year because it kicks in at a higher level resulting in an image that is brighter overall.The increased colour accuracy of the 3D LUTs resulted in improved tracking against Rec. 2020, within the limitations of the panel's native colour gamut. As we mentioned earlier, using the Auto Colour Gamut ensures that the B7 is precisely tracking whichever colour gamut the incoming signal is using. Although HDR uses a Wide Colour Gamut, don't be tempted to select the Wide Colour Gamut setting because that is just the native colour space of the panel. The B7 panel delivered an impressive 72% of the Rec. 2020 colour space, which is actually slightly more than we measured on the E7.
This improved colour accuracy also applied to the performance against DCI-P3 within Rec. 2020, with the colours all tracking their targets very closely and the B7 measured 96% of DCI using the 1931 coordinates and 99% using the 1976 coordinates, which again was slightly more than the E7. The same was true when it came to the colour volume which, using the relative CIE L*a*b* approach with 140 data points, delivered 122% against Rec. 709, 81% against DCI-P3 and 55% against Rec. 2020. Alternatively with the Perceptual Colour Volume, which uses the PQ EOTF out to 10,000nits, Rec. 2020 colour gamut, ICtCp colour graph and 393 data points, we measured an MDC (Millions of Distinguishable Colours) number of 348.
The B7 delivered a great HDR performance and even beat the E7 in some measurements
Black Levels and Contrast RatiosThe black measurements for the B7 were zero, which meant that for both the on/off and ANSI tests the effective contrast ratio was infinity. No surprise there, deep blacks are one of the major strong points of OLED technology, but it was good to see that LG have made improvements in the area just above black. In the past OLED TVs have struggled to deliver detail just above black because of the absolute nature of the technology’s black levels. This sudden change from total black to an image has resulted in crushed shadow detail but LG have applied a new algorithm that uses higher bit resolution and revised dithering to improve the visible detail above black. LG have also added a new NBO (Neutral Black OLED) polarising filter to the existing anti-reflection filters to enhance the perceived blackness and better reduce reflections from ambient light.
Screen UniformityThe screen uniformity was excellent with no dirty screen effect (DSE) or discolouration in evidence on a 100% white test pattern. We used 1 to 5% grey test patterns to check for any dark edges or vignetting and there was none apparent on the B7 that we were testing, which we should stress is a retail sample. However there was slight banding present but in fairness we have seen this on every OLED TV we've tested and it was less obvious than on the Sony A1 or Panasonic EZ1002. We should also stress that this banding wasn't apparent when watching normal content. Last year's OLED TVs also suffered from revealing macro-blocking within the dark parts of content, as well as contour lines because of the gaps in the greyscale in the dark part of the content. To mitigate this issue LG use a de-contour filter, which has removed noise and macro-blocking, thus improving the clarity of dark scenes.
Motion HandlingPerhaps the subject that generates the most debate is motion handling, not only because people perceive motion differently but because, along with video processing, it's an area where different manufacturers can have a greater impact. In testing we found the motion handling on the B7 to be the same as the E7 with around 300 lines of motion resolution with TruMotion turned off. Some people might criticise that but in reality these measurements are typical for both LCD and OLED, which means there is no current alternative. It's also worth pointing out that the motion handling of an OLED is still superior to LCD, despite the similarity in the basic measurements.
As we mentioned, different people perceive motion differently and we actually thought the motion on the B7 was very good, with football and other fast paced sports appearing very watchable without TruMotion engaged. However we do appreciate that some people struggle with any form of judder and using the TruMotion feature will increase motion resolution to nearer 1000 lines with either the Clear or Smooth settings. This will introduce excessive smoothing and the dreaded 'soap opera effect' but this won't necessarily be an issue with sports content.
For movies we would recommend either turning TruMotion off entirely or experimenting with the User setting, which allows you to customise the amount of Deblur and Dejudder. This approach will allow you to increase the motion resolution without adding unnatural smoothing that would rob a movie of its film-like quality. However if you do decide to use TruMotion be aware that the process of creating additional frames may well result in smoother perceived motion but it can also introduce other artefacts into the image.
Standard Dynamic Range ContentWe started by watching some standard definition content, primarily to test the deinterlacing and upscaling capabilities of the B7 rather than because we actually watch much standard definition content these days. However if that still constitutes a large part of your viewing material then the good news is that the B7 includes some excellent video processing that effectively deinterlaced and scaled standard definition content to match the 4K screen. The smaller 55-inch screen size also helped and macro blocking or artefacts present in the actual broadcasts were less obvious than on the 65-inch E7. When we used a better quality standard definition source like a DVD, the B7 was able to deliver some extremely watchable images.
Thankfully these days most of the content we watch is at least in high definition and here the B7 got a chance to strut its stuff, with good quality broadcasts looking excellent. We found that the snowy wastes of Fargo were nicely reproduced on the B7, whilst BBC wildlife documentaries often looked stunning, as did much of the photography on Springwatch, which we've been forced to sit through on a nightly basis. When it came to TV dramas the B7 delivered deep blacks where necessary but retained fine detail in the shadows. The processing was able to scale the high definition images to match the 4K panel, retaining a natural and realistic appearance. Thanks to World Cup qualifiers and the Lions Tour we have recently been watching a lot of football and rugby, both of which looked great on the B7 with good motion handling and no signs of annoying banding. The LG also handled the video streaming services well, with both Netflix and Amazon delivering marvellous looking images with well-shot shows such as Better Call Saul and American Gods.
However the best high definition source is Blu-ray and here the B7 really excelled, taking the progressive images and scaling them to match the Ultra HD panel. The results were always impressive with Rogue One looking particularly good, especially during the many darker sequences during the first half of the film. Although the later scenes on Scarif also looked excellent and the battle in orbit was bursting with detail as stars twinkled in the blackness of space. The B7's excellent greyscale, gamma and colour accuracy all helped to deliver lovely images that really showed how good an OLED TV is when it comes to standard dynamic range content.
HDR10 ContentSo what about high dynamic range content? Well the B7 delivered a great performance here as well, no doubt thanks to the pixel level precision of its specular highlights and its colour gamut delivering nearly 100% of DCI-P3 with great accuracy. This meant that regular test films like The Revenant and Sully retained a saturated but natural appearance, whilst the 10-bit encoding meant that the images were also free from banding, the 24p was handled well and, thanks to their 4K digital intermediates (DI), they also looked incredibly detailed.
We watched the Ultra HD Blu-ray release of John Wick and the B7 did a fantastic job of reproducing the stylised colour schemes and frenetic action. This film also used a 4K DI and the images were wonderfully detailed with no banding or other artefacts to ruin the enjoyment. The nighttime scenes were also reproduced very effectively, delivering deep blacks but retaining the details in shadows. When it came to our favourite test disc Planet Earth II, the results were just as good with stunning photography, great use of HDR and incredible levels of detail. The B7 did a marvellous job of reproducing the colours of the natural world, whilst also delivering peak highlights with precision and retaining plenty of detail in the nighttime scenes.
We were pleased to see that the B7 correctly tone mapped the sun behind the mountain in the 'Arriving in Neverland' scene in Pan, so that the disc of the sun was visible within its glow. It is often pointed out that an LCD TV will have advantages in areas like peak brightness and the overall picture level, which is true, but the pixel-level precision of an OLED combined with its deep blacks and superior shadow detail do help to mitigate any limitations in brightness. The B7 was certainly an excellent performer when it came to HDR, producing some lovely images.
The only area where the B7 occasionally struggled was with darker films like Underworld: Blood Wars because in order to retain the specular highlights the rest of the image could appear rather dark. However LG's approach to tone mapping is intended to retain the content creator's original intention and we would rather a slightly darker image than have detail clipped in the highlights. This is essentially a limitation of the static metadata used on HDR10 content and would undoubtedly be helped by the addition of Dolby Vision, where its use of dynamic metadata allows the encoding to adjust from scene to scene.
Although the Dolby Vision upgrade for our Oppo UDP-203 has been released we were unable to test the format on the B7 because our copies of Despicable Me and Despicable Me 2 (the first Ultra HD Blu-rays to include Dolby Vision) were delayed and didn't arrive until after the TV had been collected. However we will test this new feature just as soon as we can and discuss any differences between HDR10 and Dolby Vision in a separate article.
LG OLED55B7V Video Review
Sound QualityIf there was one area where the B7 disappointed slightly it was in terms of sound quality, especially compared to the E7. The more expensive LG OLED has a built-in soundbar that delivered a great performance and although the B7 has a 2.2-channel sound system with 40W of amplification, by comparison it sounded thin and insipid, lacking any real presence or depth. The smaller 55-inch screen size also meant that the sense of stereo separation and the width of the front soundstage was limited. The sound quality was certainly adequate enough for basic TV watching and given how slim the B7 is no one can expect miracles. Dialogue was clear and focused but overall the midrange was thin and the bass non-existent. When you consider the quality of the images on display, we would strongly recommend investing in an outboard audio solution to compliment your new OLED TV.
This year LG have added Dolby Atmos support to their OLED range with the idea that the psychoacoustic processing will add a greater sense of immersion from stereo speakers. In testing we found that whilst the processing did create a greater sense of presence to the audio, when watching actual Dolby Atmos demos that we were familiar with, we knew how limited the reproduction really was in comparison. This was particularly true of a sequence where thunderous bass was supposed to rumble around the room but in reality there was absolutely nothing. We do think that this kind of Dolby Atmos support is an interesting feature that can help to mask the audio limitations of ultra-slim TVs but it will never replace a proper Dolby Atmos setup.
MORE: What is Dolby Atmos
The 21ms input lag makes the B7 a great choice for gamers
Input Lag & Energy ConsumptionLG have seriously improved the input lag performance of their OLED TVs this year and using our Leo Bodnar tester we measured a lag of 21ms in Game mode which is the same as the E7. This is great news for gamers, who will also be glad to hear that the low lag applies to 1080p or 4K gaming regardless of whether it is in SDR or HDR. As an added bonus the B7 can also accept 4:4:4 signals correctly if you rename the input PC and it can support 1080p at 120Hz, which should please PC gamers. We certainly had some enjoyable sessions on Horizon Zero Dawn on our PS4 Pro and the 4K and HDR images looked fantastic.
In terms of the B7’s energy consumption it proved to be comparable to other OLED TVs that we have reviewed recently and using a full window 50% white pattern we measured the Eco picture mode at 100W, our calibrated ISF mode at 70W and the HDR mode at 128W.
How future-proof is this TV?
4K Ultra HD Resolution HDR Support Colour Space (percentage of Rec.2020 - 100% best) 72% 10-bit Panel HDMI 2.0a Inputs HDCP 2.2 Support HEVC Decoding 4K Streaming Services Smart TV Platform Picture Accuracy Out-of-the-Box (score out of 10) 8 What do these mean?
- Superb blacks and contrast ratio
- Excellent dynamic range
- Impressive image accuracy
- Improved detail just above black
- Effective video processing
- Dolby Vision support
- Attractive design
- Very low input lag
- Very minor banding just above black
- Sideways inputs too close to edge
LG 55B7 4K OLED TV Review
Should I buy one?The LG B7 makes a mockery of any suggestion that it's an entry-level model by offering an impressive design coupled with great features and performance. It has the ultra-slim shape, minimalist appearance and classy finish of a high-end TV and more features than any other OLED on the market, unless that OLED also happens to be made by LG. So you not only get support for every version of HDR including Dolby Vision but you also get audio processing courtesy of Dolby Atmos. To be fair, sound quality isn't the B7's strong point but the Magic remote and WebOS 3.5 smart platform are both excellent, whilst a 21ms input lag is bound to please gamers. However where the B7 really excels is in terms of picture quality, delivering superb images that are the equal of any other OLED in LG's 2017 range and thus making the OLED55B7 fantastic value for money. As things currently stand no other Ultra HD 4K OLED TV offers such a winning combination of features, performance and price, making the B7 a definite Best Buy.
What are my alternatives?The obvious alternative is LG's own OLED55C7 which appears to have an identical set of specifications and price, with the only difference being a sloped rather than curved stand. Although if you'd like an alternative to an LG model then the Philips 55POS901F is a serious contender that offers a really impressive image, excellent build quality, Ambilight and a built-in soundbar. The POS901 retails for a very reasonable £2,499, making it £500 cheaper than the B7 but the Philips doesn't support Dolby Vision. If you're prepared to spend a bit more then the LG OLED55E7 is a superb TV with a gorgeous Picture-on-Glass design, high-end remote and a built-in soundbar but the picture quality is exactly the same as the B7. At that price point you could also consider the excellent Sony KD-55A1 with its beautiful design, acoustic surface and Dolby Vision support or the Panasonic TX-55EZ952, although like the Philips 901F the latter doesn't support Dolby Vision.
MORE: Read All OLED TV Reviews
Suggested retail price when reviewed: £2,999.00
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