Both TVs provide standard built-in audio performance suitable for regular usage, though external speakers can enhance the experience. Both TVs come in similar screen sizes, making them suitable for comparable viewing setups and room environments. Both TVs come with smart platforms that support popular streaming apps and voice control features. Both models support NA resolution, ensuring sharp picture quality with detailed visuals for movies, shows, and gaming. Samsung CS21C370 and Samsung CS21K45 are well-equipped smart TVs that aim to provide a balance of picture quality, performance, and smart capabilities. Both TVs offer adequate brightness levels suitable for most indoor lighting conditions. Samsung CS21C370 and Samsung CS21K45 offer different motion rates (50 Hz vs 60 Hz), which can impact smoothness during fast-moving scenes like sports and gaming. In general, both TVs cater to modern entertainment needs, including streaming, gaming, and everyday viewing.

Verdict: Both TVs are strong contenders, and your final choice should depend on your preference for screen size, motion performance, and smart features.