Comparison LG 75SM9900 75 " vs LG 75SM9000 75 "

Screen resolution - its size in pixels horizontally and vertically. Other things being equal, a higher resolution provides better image quality, but such a screen costs more and requires relevant content.

The set of resolutions found in modern TVs is quite extensive, but they can be roughly divided into several groups: HD, Full HD, Ultra HD 4K, Ultra HD 5K and Ultra HD 8K. Here are the main features of each option:

— HD. Screens designed for HD 720p. The standard frame size in such a video is 1280x720, however, for a number of reasons, most HD TVs have somewhat larger sizes — 1366x768. In addition, this category usually includes models with resolutions from 1280x768 to 1680x1050, as well as 1024x768 screens. In general, HD 720p resolutions are mostly found on low-cost TVs with relatively small screens.

— Full HD. TVs designed for Full HD 1080p video, with a frame size of 1920x1080. Most models from this category have exactly this screen resolution — 1920x1080; other options are noticeably less common — in particular, 1920x1200 and 2560x1080. In general, Full HD screens provide good detail at a relatively low cost, making them extremely popular in mid-range models and inexpensive large-format TVs.

— Ultra HD 4K. This format provides different options in resolutions, however, for TVs, the actual stan...dard is 3840x2160, other options are almost never found. In general, this is a fairly high resolution, which is typical mainly for premium models; a common feature of such models is the large size — from 40" and more.

— Ultra HD 5K. The Ultra HD image format is more advanced than 4K, but it is extremely rare in TVs — these are mainly ultra-wide models with a resolution of 5120x2160.

— Ultra HD 8K. A standard that assumes a size of about 8K pixels horizontally; one of the options for this resolution, found in TVs — 7680x4320. Thus, UHD 8K is twice the size of 4K on each side and four times the total number of pixels, resulting in extremely sharp and detailed images. On the other hand, such screens are very expensive, despite the fact that nowadays even 4K is already considered a very advanced standard. Plus, there are not many video devices and content that meet this standard. Therefore, 8K TVs are still extremely rare, they include mostly high-end flagship models with a size of at least 65".

TV support 4K upscaling feature.

This feature is only found in models with 4K screens and above (see "Resolution"). It allows to increase the resolution of the original image to 4K (3840x2160), if it is initially lower — for example, to view a movie in 4K that was originally recorded in Full HD (1920x1080). This is not just about “stretching” the image to fill the screen (all TVs are capable of doing this), but about special processing, due to which the actual video resolution is increased. Of course, such video will still be inferior to content originally recorded in 4K; however, upscaling provides a noticeable improvement in quality over the raw signal.

TV support 8K upscaling feature.

This feature is only found in models with 8K resolution screens. It allows to increase the resolution of the original "picture" to 8K (7680x4320 or similar), if it is initially lower — for example, to view a movie in 8K that was originally recorded in 4K (3840x2160) or even Full HD (1920x1080). This is not just about “stretching” the image to fill the screen (all TVs are capable of doing this), but about special processing, due to which the actual video resolution is increased. Of course, such video will still be inferior to content originally recorded in 8K; however, upscaling provides a noticeable improvement in quality over the raw signal.

The highest frame rate supported by the TV.

Note that in this case we are talking specifically about the screen’s own frame rate, without additional image processing (see “Index of dynamic scenes”). This frequency must be no lower than the frame rate in the video being played - otherwise there may be jerks, interference and other unpleasant phenomena that degrade the quality of the picture. In addition, the higher the frame rate, the smoother and smoother the movement in the frame will look, and the better the detail of moving objects will be. However, it is worth noting here that playback speed is often limited by the properties of the content, and not by the characteristics of the screen. For example, films are often recorded at a frequency of only 30 fps, or even 24 - 25 fps, while most modern TVs support frequencies of 50 or 60 Hz. This is enough even for viewing high-quality content in HD resolutions (speeds above 60 fps in such video are extremely rare), but there are also “faster” screens on the market: 100 Hz, 120 Hz and 144 Hz. Such speeds, as a rule, indicate a fairly high class of the screen; they also often imply the use of various technologies designed to improve the quality of dynamic scenes.

TV support for one or another brightness / contrast enhancement technology.

Usually, in this case, software image processing is implied, in such a way as to improve brightness and/or contrast (if necessary). Specific processing methods may be different — in particular, in some cases we are actually talking about turning standard content into HDR (see above), and some manufacturers do not specify technical details at all. The effectiveness of different technologies can also be different, and besides, it is highly dependent on the specific content: in some cases, the improvement will be obvious, in others it may be almost imperceptible. Also note that this feature is not always useful, so in most models it is turned off.

A decoder can be broadly described as a standard in which digital audio (often multi-channel) is recorded. For normal playback of such sound, it is necessary that the corresponding decoder is supported by the device. Dolby Digital and DTS were the first in multi-channel decoding, gradually improving and introducing new features. The final stage for 2020 is Dolby Atmos and DTS X decoders.

– Dolby Atmos. A decoder that uses not a rigid distribution of sound across channels, but the processing of audio objects, due to which it can be used with almost any number of channels on a reproducing system — the sound will be divided between channels so that each audio object is heard as close as possible to its proper place. When using Dolby Atmos, ceiling speakers (or speakers facing the ceiling) are highly desirable. However, in extreme cases, you can do without them.

— DTS X. An analogue of the Dolby Atmos described above, when the sound is distributed not through individual channels, but through audio objects. The digital signal contains information about where (according to the director's intention) the object audible to the user should be and how it should move, and the processor of the reproducing device processes this information and determines exactly how the sound should be distributed over the available channels in order to achieve the required localization. Thanks to this, DTS X is not tied to a specific number of audi...o channels — there can be as many as you like, the system will automatically divide the sound into them, achieving the desired sound. Also note that this decoder allows you to separately adjust the volume of dialogues.

The ability to display on the TV screen "pictures" from several sources at once. Usually, in the picture-in-picture mode, a small window is displayed in the background of the main image (or several such windows), which is displayed in full screen, in it you can see an additional image. One of the most popular ways to use this “multitasking” is to skip commercial breaks in TV broadcasts: for this time, you can switch the main image to a more interesting channel, and leave the ad in the auxiliary window to not miss the end of the commercial and continue watching. It is worth considering, however, that the images for each window must come from different sources — in other words, it will not work to turn on two channels at the same time from one tuner.

The amount of memory installed in the TV to store content in the device. The larger size is especially relevant given that modern TVs allow the installation of additional applications that enhance the capabilities — and these applications also require space. However, do not forget that the TV system also requires space. And manufacturers by the volume can indicate both the total value and the free memory calculated for installing applications. And the volume itself can vary from 4 GB to 16 GB or more. However, a TV with 8 GB memory may be the best option.

The amount of random access memory (RAM) installed in the TV.

In general, this volume is selected by the manufacturer in such a way that the device can normally cope with the tasks that are claimed for it. On the other hand, all else being equal, more RAM ( 3 GB, 4 GB or more) usually means faster performance. This parameter is especially important if the TV runs on Android: such firmware allows the installation of additional applications that may have rather high requirements for RAM. However, TVs with 2 GB of RAM and below can also not be discounted — they just can't pull high-demanding applications. But do not forget that this is a TV, not a laptop.