LG CineBeam S Review: Pocket-Sized 4K, Real Compromises

Almost every ultra-short-throw projector is a large slab of a thing that you position once and never move again. The LG CineBeam S is the exception: a 4K triple-laser UST small and light enough to go in a rucksack. That single fact is the reason to consider it — and it is also the reason for nearly every compromise that follows.

Underneath is a DLP chip with a triple-laser light source, reaching 4K Ultra HD (3,840 x 2,160) by pixel-shifting. That resolution in this size is genuinely unusual.

The projection range is 40 to 100 inches, which is modest next to rivals that stretch to 150, but consistent with the body. The throw ratio is 0.25:1, so it sits very close: measurement put it 33 cm from the screen for a 2-metre-wide image, roughly 90 inches diagonally.

As with any UST, you need a genuinely flat surface — or better, a tensioned ALR/CLR screen — or you will see distortion and shadowing. Budget for that if you do not have a suitable wall.

Three of them matter, and they are not evenly distributed. One is a dealbreaker for some buyers, one is a nuisance, and one is only a problem if you care about accuracy.

The sound is the dealbreaker. The built-in speakers are described bluntly in testing as very poor: thin, critically short of bass, and not even the equal of a small portable Bluetooth speaker. They exist to make a noise, nothing more. A soundbar or a Bluetooth speaker is not an upgrade here — it is a requirement, and it should go in your budget from the start.

Brightness is the nuisance. Measured HDR peak was 62 cd/m². Rivals in this price bracket generally exceed 150 cd/m², and the brightest UST models go past 250. In practice that means a properly darkened room, not a living room with the curtains half drawn. One small consolation of the modest output: no laser speckle was observed.

Colour accuracy is the connoisseur's complaint. Even in Filmmaker Mode, average delta E measured 7.8 in SDR against a reference of 2 to 3, so colours visibly drift. Colour temperature came in at 6,000 K against the 6,500 K standard, which leaves images slightly yellow, and gamma measured 2.0, which is too low and lifts greys so the picture looks a little flat. The saving grace is a full colour management system for saturation, hue and luminance — so it can be corrected, if you are willing.

There is real quality here. Sharpness is convincing for something this compact, and 4K is a genuine step up from the 1080p mini-projectors this competes with on size, though the corners are softer than a full-size premium model.

Colour volume is a strength: 99.4% of DCI-P3 and 95.3% of Rec.2020, courtesy of the triple laser. Colours are rich and saturated even when they are not accurate.

Contrast is the figure that needs a caveat. It measured 2,180:1, which reads as a good result and places it above some larger rivals. In actual film viewing, though, contrast was judged not very good at all, with noticeably greyed blacks. Treat the number as theoretical rather than what you will see.

On HDR, support stops at HDR10 and HLG — no HDR10+ and no Dolby Vision, which is a real omission at this price. HDR delta E climbed to 22.7, a long way from reference.

One setting to change on day one: the motion compensation is aggressive, and even on its Low setting the soap-opera effect stays visible on films. Most people will want it off, accepting a little more judder on panning shots.

Measured input lag was 51.1 ms. For context, a Hisense C2 Ultra manages 22.6 ms and a Formovie Theater Premium 18.8 ms. You will feel the delay between pressing a button and seeing the result, even in casual play. Refresh is capped at 60 Hz. This is a film projector, not a gaming one.

Setup is the strongest practical feature. Automatic keystone correction and autofocus are still uncommon on ultra-short-throw models, and having both makes moving it between rooms genuinely realistic.

Connections are minimal: HDMI eARC and USB-C, the latter usable for charging or for connecting a laptop or phone. AirPlay, Miracast, Bluetooth and Wi-Fi cover wireless streaming. That is the essentials and no more — if you have several sources to plug in, this is not the projector for you.

The interface is webOS, in an older build than LG's televisions run. The native streaming apps are all present, but menu transitions were found to lack fluidity, with waits moving between screens, and you cannot install third-party apps such as VLC the way you can on Google TV.

The remote is a disappointment: basic, cheap in the hand, no Bluetooth and no backlight — an odd omission for a device designed to be used in a dark room.

Noise measured 37.5 dB at one metre. The quietest projectors in this class sit below 33 dB, so the small fans are audible — and with audio this weak, there is nothing to mask them.

Running costs are low. Average consumption measured 53.4 W, well under brighter and bulkier models. It charges over USB-C at 65 W, though it still ships with a conventional power brick rather than a phone-style plug.

Buy it if space or portability is the constraint that actually governs your decision — a small flat, a room where a permanent projector will not fit, or a genuine need to carry it between places. Nothing else at this size gives you 4K from a triple laser, and setup is close to effortless.

Avoid it if you want a projector for a bright room, if you are buying for gaming, if you need Dolby Vision or HDR10+, or if you are not prepared to add external sound. Larger ultra-short-throw models cost more and take more room, but outperform it on most measures that are not portability.

Truthful Reviews has not tested this projector. The measurements above — contrast, delta E, brightness, input lag, noise and power — are published figures from an independent European review of this exact model, taken with a Calibrite Display Plus HL probe and CalMAN Ultimate software; that source URL is stored as this page's editorial provenance. The UK commerce details were checked directly against the retailer's own listing.

It was £833.42 on Amazon UK and in stock when we checked on 2 August 2026. A second listing for the same model was priced at £1,209.00, so check which one you are ordering. Remember to add a screen and external audio to the real cost. Check the price on Amazon UK or search on Amazon US