One reason many of us buy a particular TV is because we trust that brand and assume the company whose name is on the front of the set is actually building it. But that's becoming less common, according to a report from market research firm IHS.

In fact, the company says, well-known name-brand TVs are increasingly relying on Chinese and Taiwanese contract manufacturers to build their sets, both to trim manufacturing costs and to secure components, such as panels, when supplies get tight. According to IHS, by the end of 2015 some 43 percent of the TVs made globally this year will be outsourced, a new industry high.

As you can see from the chart below, Vizio and Haier rely exclusively on contract manufacturing, where a third-party company does the actual production, generally from a design and specifications set by the brand. Sony is also increasingly turning to outside manufacturing. Korean brands such as LG and Samsung don't turn to outside manufacturers as often as other companies, since they want to fully utilize their in-house manufacturing capacity.

TV brands have outsourced some components for years. But the move to complete contract manufacturing is newer, especially among better-known brands. It's then up to the brand's quality assurance teams to make sure the TVs can consistently perform up to the company's benchmarks.

One downside to outsourcing is that quality can vary. That's a big reason why Consumer Reports continues to buy and test several models in each TV brand's series, rather than assuming all TV screen sizes in a series will perform similarly. Over the past few years, we've noticed more differences—sometimes subtle, sometime more dramatic—in the attributes and performance of TVs with different screen sizes, even when they're from the same series from the manufacturer.

Outsourcing is most common for entry-level sets. If you want a name-brand TV that's made by the company on the front of the set, your best bet is to buy a step-up or flagship model from a major brand. Companies reserve their best in-house capabilities for these sets, which have differentiating features such as curved 4K screens, wider color gamuts, and smart TV platforms.

Buying a TV made by a contract manufacturer doesn't necessarily mean you're getting a lesser product, since major brands need to maintain quality control over these sets or they risk diminishing their brands. Just make sure that the warranty is the same as on other sets from the company so that if you do have a problem, you'll get the same level of service as with any other TV made by the company.

—James K. Willcox

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