Comparison LG 65SJ810V vs LG 65UJ750V

TV support for Upscaling function. This feature is only available on models with 4K and 8K resolution screens.

Upscaling to 4K allows you to increase the resolution of the original “picture” to 4K (3840x2160), if it was initially lower - for example, viewing a movie in 4K that was originally recorded in Full HD (1920x1080). In this case, we are not just talking about “stretching” the image to fill the entire screen (all TVs are capable of doing this), but about special processing, thanks 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 compared to the raw signal.

Upscaling to 8K works on the same principle, only relevant for 8K TVs.

The true panel frequency of a TV without marketing enhancements and interpolation; today there are two classes: 50/60 Hz and 100/120 Hz. The pair of 50 and 60 Hz exists due to historical video signal standards (Europe 25/50, USA/Asia 30/60), with modern TVs typically accepting both. It is reasonable to consider the 100/120 Hz pair as one: it is the same high-end hardware platform, simply operating in multiples of its "native" content (100 Hz for 50 Hz sources, 120 Hz for 60 Hz). This class provides smoother motion in sports and 24p movies (at 120 Hz — in a multiple of 5:5 without stuttering) and unlocks 4K@120 Hz/VRR for gaming; 50/60 Hz remains the basic option for TV and streaming without gaming ambitions.

— Coaxial (S/PDIF). An interface for transmitting audio in digital format, which allows to transmit multi-channel audio via a single cable with an RCA connector (“tulip”). In terms of resistance to interference, this standard is somewhat inferior to the optical one (see below) — this is due to the fundamental differences between these interfaces. On the other hand, electrical cable is more reliable than optical fibre and is not as sensitive to pressure and bending.

— Optical. An output for transmission of a digital audio signal on a fibre optic cable; allows the transmission of multi-channel audio. Notable for its complete insensitivity to electromagnetic interference. On the other hand, fibre optic cable is quite fragile, it must be protected from bending and strong pressure.

— Mini-Jack (3.5 mm) for headphones. Standard 3.5mm headphone jack. Headphones can come in handy if you need to keep quiet and you can’t use the TV speakers – for example, at a later time of the day; or vice versa, if the environment is noisy and the sound of the TV is hard to hear. Most modern "ears" use a mini-Jack plug, so this connector is the standard headphone output in TVs. And in some models, this output can also be used as a linear output — for example, to connect individual speakers, a sound recording device, etc.

— Subwoofer. A separate output for connecting...a subwoofer to a TV is a speaker for reproducing low and ultra-low frequencies. Audio systems without subwoofers usually reproduce these frequencies quite poorly. The use of subwoofer allows you to achieve the most deep and rich sound, which is especially important when watching movies with a lot of special effects or high-quality recordings from concerts. At the same time, it is worth noting that such outputs are quite rare in TVs: it is assumed that a full-format external audio system is more suitable for a demanding listener than a separate subwoofer.

— Line. Standard analogue audio interface; usually, provides the transmission of two-channel stereo. It is used primarily to connect active speakers and other audio equipment (for example, audio receivers or power amplifiers) to TVs. It can use different types of connectors, but most often it provides either a 3.5 mm mini-Jack or a pair of RCA jacks for tulip cables. Note that it is a separate line output that is meant here; in some models, this function can be performed by a 3.5 mm headphone jack (see above), but for them the presence of a line-out is not indicated.