The TCL 55S421 is a 55-inch 4K UHD smart TV that offers a premium viewing experience at an affordable price point. Part of TCL's S421 series, this 2021 model features a slim, modern design and comes equipped with the user-friendly Roku TV platform.

With stunning 4K resolution and High Dynamic Range (HDR) support, the 55-inch TCL 55S421 delivers immersive picture quality and vivid, accurate colors on its large LED display. The TV has a 3840 x 2160 resolution and supports HDR content in HDR10 format.

Powered by the intuitive Roku operating system, the TCL 55S421 provides easy access to over 5,000 streaming channels through the Roku Channel Store. Built-in Wi-Fi allows for seamless streaming, while the included Roku remote makes navigating all your entertainment options a breeze.

For its price point, the TCL 55S421 offers robust smart TV capabilities and strong 4K UHD picture performance that punches above its weight. Read on for a more detailed overview of the key features and capabilities of this 55-inch 4K smart TV.

Design

The TCL 55S421 features a simple, minimalist design with thin bezels around the display for a modern look. The TV has a basic black plastic body with silver trim along the bottom. The stand consists of two wide-set V-shaped metal feet. While the design is fairly basic, the thin bezels help draw attention to the 55-inch screen and make the TV seem larger than it is. The slim profile also allows it to blend in seamlessly with any room decor.

At just 2.99 inches deep, the TV doesn't take up much space on your media console. The slim design provides a streamlined, uncluttered aesthetic that looks great in both contemporary and traditional settings. The minimalist style places emphasis on the picture quality rather than fancy cosmetic frills. For those seeking a no-fuss 4K TV, the pared-down design of the TCL 55S421 keeps focus on the viewing experience. The simple yet elegant design allows the 4K picture to take center stage, providing an immersive viewing experience in any setting.

While the TCL 55S421 has a basic design, some other 55-inch TVs on the market feature more premium styling and build quality. For example, the LG 55UR9000PUA 55-inch TV has a sophisticated gallery design with an ultra-thin bezel and brushed metal finish. The minimal bezel is almost unnoticeable, putting all focus on the cinema-like 4K display. It comes with a stylish metal stand that adds stability while complementing modern decor. For those wanting more aesthetic flair from their 55-inch 4K TV, the LG 55UR9000PUA delivers with its artful, high-end design.

Display Quality

The TCL 55S421 55 inch 4K UHD LED smart Roku TV features an impressive 4K Ultra HD (2160p) resolution display. With over 8 million pixels on the screen, the 4K resolution delivers stunning clarity and crisp details on the large 55 inch screen.

4K resolution is 4 times the resolution of Full HD 1080p, resulting in a major boost in image quality. Viewers can easily see the extra fine details in content mastered in 4K. The higher resolution display makes the picture look lifelike.

In addition to 4K resolution, the TV also supports High Dynamic Range (HDR) including HDR10 and Dolby Vision. HDR produces a wider range of brightness and colors, creating a more dynamic and immersive viewing experience. The expanded color gamut and increased contrast ratio make colors appear more vibrant while preserving details in the darkest and brightest areas of the picture. HDR content brings out the true visual quality the display is capable of.

With the combination of 4K and HDR, the TCL 55S421 delivers excellent picture performance that does justice to your favorite movies, shows and games. The sharpness, clarity and image quality allow you to get the most out of 4K streaming and Ultra HD Blu-ray discs.

While the TCL 55S421 offers great 4K picture quality, there are other high-end 4K TVs to consider as well, like the SAMSUNG QN55S90C. This 55-inch Samsung 4K TV features a curved screen design and quantum dot technology for even better color performance. The quantum dots produce over a billion color shades for very accurate and saturated colors. In addition, the curved screen provides an immersive viewing experience by reducing reflections and enhancing depth perception.

The SAMSUNG QN55S90C also has a 240Hz refresh rate for fast motion scenes, low input lag for gaming, and Samsung's smart TV platform. With Quantum Dot technology, the SAMSUNG QN55S90C delivers cinematic image quality with colors that pop. So while the TCL 55S421 provides great 4K resolution at an affordable price, premium 4K TVs like the SAMSUNG QN55S90C push the limits of what's possible with display technology today. When comparing 4K TVs, be sure to consider the display quality, HDR capabilities, smart features, and overall design.

Smart TV Features

The TCL 55S421 comes loaded with smart capabilities powered by the intuitive Roku TV interface. This provides easy access to thousands of streaming channels and apps.

With Roku TV, you get a simple home screen that you can customize with your favorite streaming services and connected devices. The interface is very user-friendly, with large icons and options laid out in an easy-to-navigate manner.

Some of the most popular streaming services like Netflix, Hulu, Prime Video, Disney+, HBO Max and many more are available directly from the home screen. You can log into your accounts and access a huge library of shows, movies and documentaries.

The Roku Channel also offers free ad-supported movies, TV shows and live news in one place. With Roku Search, you can find titles across all your streaming services and connected devices just by typing in the name.

Overall, the excellent smart TV capabilities, vast app selection and intuitive interface make streaming a breeze on the TCL 55S421.

Audio Quality

The TCL 55S421 has decent sound quality for an entry-level 4K TV. The two 8W speakers provide adequate volume to fill a medium to large room. Dialogue sounds clear and distinguishable. However, the lack of Dolby audio support means the sound quality isn't as immersive or dynamic as higher-end models. The speakers lack the power to take full advantage of action sequences and music playback. There's no way to connect a separate soundbar or speaker system either. Overall, the audio is acceptable for everyday TV watching, but an external audio system is recommended for the best sound experience.

Ports and Connectivity

The TCL 55S421 comes with a good selection of ports and connectivity options. On the back of the TV, you'll find:

• 3 HDMI ports - These allow you to connect devices like Blu-ray players, game consoles, streaming sticks, etc. 3 HDMI ports is pretty standard for a budget 4K TV these days.

• 1 USB port - The USB port allows you to connect external devices like hard drives to view photos/videos or record live TV. Only having 1 USB port is disappointing, as it limits your connectivity options.

• Digital audio output - Optical audio out allows the TV audio to be sent to an external audio system, like a soundbar or AV receiver.

• Ethernet - For a wired internet connection if you don't want to rely on WiFi.

• RF input - For connecting cable/antenna.

The TV also has built-in WiFi for connecting to your home network wirelessly. The WiFi is 2.4GHz only, there is no 5GHz support.

Overall the port selection is decent but unremarkable. The lack of a second USB port is a negative, but you get the essentials covered.

Remote Control

The TCL 55S421 comes with a simple remote control that is easy to use. The remote is smaller than traditional remotes, with a clean button layout that makes it easy to find the buttons you need.

The most frequently used buttons like power, volume, and channel change are at the top of the remote for quick access. There is a directional pad in the middle with a select button, making it easy to navigate menus and selections on the TV screen.

Dedicated buttons for popular streaming apps like Netflix, Hulu, ESPN+, YouTube, and Sling TV are located at the bottom of the remote. This allows you to quickly launch these apps instead of having to search for them through the smart TV interface. The streaming service buttons are really convenient when you just want to start watching a show right away.

Overall, the remote that comes with the TCL 55S421 has an intuitive design optimized for accessing streaming content. The no-frills button layout prioritizes the controls you need the most in a compact form factor that feels comfortable in the hand.

Performance

Overall, the TCL 55S421 offers good performance and picture quality for its price point. The 4K resolution delivers a crisp, detailed image, and the HDR technology produces brighter colors and more vivid contrast. While not as advanced as higher-end models, the image processor does a decent job upscaling HD content into 4K.

Motion handling could be better, as fast-moving scenes can get a bit blurry. Input lag is also higher than ideal for gaming. That said, for casual TV watching and streaming movies, most users will find the picture quality quite pleasing. The blacks are deep, colors are vibrant, and 4K video looks sharp.

For a budget 4K TV under $500, the TCL 55S421 provides good value given its performance. It may not have all the bells and whistles of premium models, but it delivers solid picture quality for everyday entertainment. Just don't expect it to compete with high-end 4K sets. Overall, most buyers will be satisfied with the performance and visuals from this affordably priced TCL model.

Pros and Cons

The TCL 55S421 offers a lot of value and features at an affordable price point. Here are some of the key pros and cons:

Pros

• Great value: The 55S421 is very affordable for a 55-inch 4K TV with Roku TV built-in. It's hard to find similar sized 4K TVs at this price range.

• Roku TV: The Roku platform is easy to use and offers thousands of streaming apps and channels. You get access to all your favorite streaming services in one place.

• 4K and HDR support: With 4K resolution and HDR support (HDR10 and HLG), the 55S421 delivers good picture quality and color for most non-HDR and some HDR content.

Cons

• No local dimming: Without local dimming, the 55S421 can't achieve high contrast for HDR content. Black levels aren't very deep.

• Basic sound: The built-in speakers only provide basic sound quality. You'll want to pair the TV with a soundbar or speakers for an immersive audio experience.

Conclusion

The TCL 55S421 is a great budget 4K TV option with good picture quality, smart TV capabilities, and a sleek modern design. It delivers vibrant 4K resolution in a 55-inch screen size at a very affordable price point.

The 4K Ultra HD resolution provides sharper, more detailed images compared to 1080p Full HD. HDR support also helps to produce a wider range of colors and brightness levels. Movies, shows, sports, and games all look great on this display.

For smart features, the built-in Roku platform gives you access to thousands of streaming apps and channels. It's very user-friendly and intuitive to navigate. You can also cast content from your mobile device to the TV screen.

The minimalist design looks good in any room with thin bezels and metal accents. The TV is easy to set up with the included stand or can be mounted on the wall. Connectivity options like HDMI, USB, and Ethernet allow you to connect external devices.

Considering its price, the TCL 55S421 packs in a lot of great features. It's a wonderful choice if you want a big-screen 4K TV on a budget. The picture and sound quality exceed expectations. For casual TV watching and streaming movies, it provides an immersive viewing experience without breaking the bank.