LG B8 vs C8 vs E8
The LG B8 vs C8 vs E8 all have an OLED panel, meaning that they are self-emissive TVs, and there is no backlight. As a result, the fundamental aspects of the picture quality such as black level and color reproduction are identical on LG B8 vs C8 vs E8. Specifically, the three LG OLED TVs have a perfect black level of 0 cd/m2 (so the contrast ratio is infinite), and near full DCI-P3 color gamut coverage (which is a color space used in HDR content). Their peak brightness with SDR content is also identical. Either the LG B8 or C8 or E8 can reach and maintain approximately 400 cd/m2 up to 70% APL (Average Picture Level), meaning that they have enough brightness headroom to be comfortably used in bright environments for watching low-to-mid APL content (i.e. the vast majority of movies and TV series). Nevertheless, it needs to be said that there is an ABL (Auto Brightness Limiter) present on all three LG OLED TVs for the purpose of preventing them to consume too much power when displaying content with preponderance of bright elements, and protecting internal components from overheating. The impact of the ABL, however, is limited to high-APL content such as hockey and winter sports during which can be observed a brightness reduction as the APL increases. The LG B8, C8 and E8 are able to reach about 150 cd/m2 on 100% APL (full-white screen), so there is still some brightness headroom even for high-APL scenes because SDR content is normally mastered to a 100 cd/m2.
The Differences: LG B8 vs C8/ E8
The LG C8 and E8 use the Alpha 9 picture processor whereas the LG B8 is equipped with the Alpha 7. As a result, the former two TVs are able to perform a quad-step MPEG Noise Reduction (with a 2-pass smooth gradation) whereas the LG B8 has a dual-step MPEG Noise Reduction (with a single pass smooth gradation). This leads to a more effective banding removal on part of the LG C8 and E8 vs B8 but given that the decontouring filters are used together with the noise reduction ones, the LG C8 and E8 are more likely to exhibit loss of fine detail (particularly with high quality content) than the LG B8. The MPEG Noise reduction setting, however, is granular so it's possible to find the right balance between minimizing banding artifacts that are present in the content, and keeping fine-detail largely intact. And given that the native bit depth of the OLED panel used in LG B8, C8 and E8 is 10-bit, you'll only need to use the MPEG Noise Reduction (which controls Smooth Gradation filters) only in case the posterisation is in the content (due to inadequate bitrate, for example) because otherwise all three LG OLED TVs are natively capable of delivering smooth gradation (due to their 10-bit panels which allow them to render over a billion color shades).
The different image processor used on LG B8 on the one hand, and LG C8 and E8 on the other, also affects some other processing techniques such as Sharpness and Depth Enhancements. The LG C8 and E8 have a Frequency-based Sharpness Enhancer, in addition to Object-based Depth Enhancer wheres the LG B8 utilizes a standard Sharpness Enhancer, and Edge-based Depth Enhancer. These picture enhancements do not need to be used when watching high quality content, so the advantage LG C8 and E8 have over the LG B8 is limited only to low resolution/quality sources. There is also a limit in how much the aforementioned picture enhancements can improve standard definition (or poorly compressed content) , especially given that the resolution of all three LG OLED TVs is 3840x2160, so some imperfections in the upscaling are bound to be noticeable.
The LG C8 and E8 have the True Color Accuracy Pro while the LG B8 has the standard version of this technology. The reason is that 17x17x17 Cube LUTs (Look-up Tables) are used on the LG B8 whereas the LG C8 and E8 have 33x33x33 Cube LUTs. The number of color coordinates that can be stored is therefore about 7.3 times greater on the LG C8 and E8 vs B8. Specifically, the LG C8 and E8 can store 35,937 color data entries vs 4,913 data entries on the LG B8. In addition to providing direct color corrections, these coordinates are used for color interpolation as well. As a result, not only more colors can be directly corrected on the LG C8 and E8 vs B8 but also the former two LG OLED TVs have to perform fewer color interpolations. Fewer calculations means that the LG C8 and E8 are less likely to produce any errors, hence the more accurate out of the box colors. That being said, all three LG OLED TVs are compatible with the CalMAN's auto calibration functionality since they allow this software to directly address their internal 3D Cule LUTs (and 1D LUTs for gamma and grayscale calibration). The CalMAN software is sold separately, and in order to perform an auto calibration you'll also need a pattern generator and colorimeter (sold separately).
Even though all three LG OLED TVs have a HEVC decoder conforming to the Main10 profile at level 5.2, meaning that they are able do decode 4K up to 120fps, the LG C8 and E8 are able to process HDR on top of 4K HFR (High Frame Rate) whereas the LG B8 cannot (but it still can handle 4K HDR or 4K HFR individually). It also needs to be said that the 4K HFR support on LG B8, C8 and E8 applies only to USB and network streaming but not to HDMI since the three LG OLED TVs have HDMI 2.0 ports that support HFR only up to 1080p resolution. In order to be able to transmit 4K@120fps via HDMI, they'd have to be equipped with HMDI 2.1 inputs.
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The Differences: LG B8/ C8 vs E8
The LG B8 and C8 have a similar design called Cinema Screen, and only differ in the supplied table top stand which is considerably wider on the LG C8 vs B8. When it comes to LG E8, however, the design is quite different from the LG B8 and C8. The Picture-on-Glass design of the LG E8, as the name suggests, has the OLED modules directly mounted on a glass back that extends almost to the surface the LG E8 is placed on. Combined with the low-profile stand, the LG E8's Picture-on-Glass design creates the impression the TV is floating in the air when mounted on a table top surface. The glass back also serves another purpose: increasing the structural strength of the ultra-thin OLED panel (without significantly increasing the overall thickness of the TV).
The LG E8 has an integrated sound bar which allows it to direct sound towards the viewer. The LG B8 and C8 have down-firing speakers so the clarity of voices and dialogues is not on par with the LG E8. It needs to be said, though, that the LG C8 has an alpine table-top stand with a cutout under the down-firing speakers designed to help redirect sound towards the viewer. The speaker system is 2.2 channel on LG B8 and C8 , and 4.2 channel on the LG E8. The dedicated tweeters and mid-range drivers on the LG E8 allow for more clear separation of high and mid-frequency sounds in comparison to the LG B8 and C8's full-range drivers. There is less variation in the bass performance since all three LG OLED TVs utilize a dual sub woofer configuration, and allocate the same amount of power (20 Watts) to their sub woofers. The total audio power output, however, is 60 Watts on the LG E8 vs 40 Watts on the LG B8 and C8.
Screen sizes and availability: