LG B4 55" vs Sony X90K 65" (Full Array LED)
The Verdict
LG's B4 OLED delivers superior contrast and color accuracy with its self-emissive pixel technology, producing perfect blacks and exceptional picture quality that OLED excels at. Sony's X90K compensates with a larger 65-inch display, brighter peak brightness (1200 nits vs 1100), and full-array local dimming that provides more uniform lighting across scenes. Gaming performance slightly favors LG with 1ms input lag versus Sony's 8ms, though both support VRR and ALLM. Sound quality leans toward LG with 40W output and Dolby Atmos versus Sony's 20W setup. Pricing proves intriguing,the 55" LG costs $100 more despite being smaller, reflecting OLED's premium positioning. For cinephiles prioritizing image quality and gaming responsiveness, LG B4 justifies the investment. Budget-conscious buyers wanting larger screen real estate should consider Sony X90K's value proposition, though it sacrifices some contrast depth inherent to LED technology.
Who Should Buy
Buy the LG B4 55" if…
- →Lowest-cost entry into LG's OLED lineup with the same perfect blacks
- →All four HDMI ports with VRR and ALLM at 4K@120Hz for gaming
- →Dolby Vision and Dolby Atmos at an entry OLED price
Buy the Sony X90K 65" (Full Array LED) if…
- →Excellent Sony image processing at a competitive mid-range price
- →Full Array Local Dimming provides solid contrast for an LED TV
- →Dolby Vision and Dolby Atmos for home theater HDR experience
Category Scores
Pros & Cons
LG B4 55"
Pros
- Lowest-cost entry into LG's OLED lineup with the same perfect blacks
- All four HDMI ports with VRR and ALLM at 4K@120Hz for gaming
- Dolby Vision and Dolby Atmos at an entry OLED price
- webOS 24 is one of the best smart TV interfaces available
Cons
- Only two HDMI 2.1 ports — the other two are HDMI 2.0 (limited to 4K@60Hz)
- α8 processor is noticeably weaker than the C4's α9 for upscaling and processing
- Lower peak brightness than the C4 or G4 — HDR highlights lack some punch
- No Wi-Fi 6, which limits wireless bandwidth in crowded network environments
- OLED burn-in risk remains a concern for heavy static-content users
Sony X90K 65" (Full Array LED)
Pros
- Excellent Sony image processing at a competitive mid-range price
- Full Array Local Dimming provides solid contrast for an LED TV
- Dolby Vision and Dolby Atmos for home theater HDR experience
- 120Hz with VRR and ALLM — capable gaming display
- Google TV with Chromecast built-in for seamless streaming
Cons
- Only 2 of 4 HDMI ports support 4K@120Hz
- 20W audio is very weak — soundbar essential
- Bluetooth 4.2 and Wi-Fi 5 are behind current standards
- Some blooming visible with full array backlighting in dark scenes
Full Specifications
| Spec | LG B4 55" | Sony X90K 65" (Full Array LED) |
|---|---|---|
| Body | ||
| VESA mount | 200 x 200mm | 300 x 300mm |
| Weight | 41.9 lbs | 46.3 lbs |
| Dimensions (w/ stand) | 48.4 x 32.1 x 10.5 inches | 57.2 x 35.3 x 12.0 inches |
| Dimensions | — | 57.2 x 33.1 x 2.7 inches |
| Audio | ||
| Output (watts) | 40 | 20 |
| Speakers | 2.0ch | 2.0ch Acoustic Multi-Audio |
| Dolby Atmos | ||
| Gaming | ||
| VRR (Variable Refresh Rate) | ||
| ALLM | ||
| Input lag (ms) | 1 | 8 |
| Display | ||
| HDR | Dolby Vision IQ, HDR10, HLG, Filmmaker Mode | Dolby Vision, HDR10, HLG |
| Size | 55" | 65" |
| Type | OLED | Full Array LED (VA LCD) |
| Resolution | 3840 x 2160 (4K UHD) | 3840 x 2160 (4K) |
| Refresh rate | 120Hz | 120Hz |
| Brightness (nits) | 1100 | 1200 |
| Smart TV | ||
| Os | webOS 24 | Google TV |
| Voice assistant | ThinQ AI, Alexa, Google Assistant | Google Assistant, Alexa |
| Processor | ||
| Chipset | α8 Gen 7 AI Processor 4K | — |
| Connectivity | ||
| Wi-Fi | Wi-Fi 5 (802.11ac) | Wi-Fi 5 |
| Ethernet | ||
| Bluetooth | 5.0 | 4.2 |
| USB ports | 3 | 2 |
| HDMI ports | 4 | 4 |
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This comparison is based on verified manufacturer specifications covering display, performance, camera, battery, and build quality. Scores are generated by analyzing specs across weighted categories on a 10-point scale. Learn more about our methodology.
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