THX was founded 35 years ago by George Lucas to help assure a certain level of consistency in the performance of commercial cinemas it has certified. Since then, THX has expanded its mandate to include the certification of consumer electronics and the development of audio technologies, such as AAA amplifiers and a spatial-audio platform.
Today, THX announces its latest project—the THX Standard website. Serving as an adjunct to the company’s consumer-electronics certification program, the new website offers the results of detailed measurements performed on various A/V products. It also provides scores based on those measurements, which follow the rigorous procedures developed for the THX certification program, as well as an overall score calculated from the individual scores. Even better, it lets you compare the scores, individual measurements, and manufacturer-provided specifications for up to three products in a table.
THX Standard is not a certification or logo program. Instead, THX scours the Internet to determine which products are the most popular, buys each product at retail, and runs its suite of tests and measurements. That suite is not as extensive as the certification tests; rather, it is a subset of the suite using the same testing equipment and procedures.
At launch, THX Standard includes five product categories: TVs, stereo (2-channel) power amplifiers, multichannel power amps, powered studio-monitor speakers, and 2.1 PC speakers. In the future, THX will add more categories, such as projectors, AV receivers, passive speakers, subwoofers, and others. It will also add products to the existing categories. As of this writing, there are 10 TVs, six 2-channel power amplifiers, four multichannel amps, 10 powered studio monitors, and nine 2.1 PC speakers on the site.
I performed a comparison of the top three products in each category. Here are the results:
According to the overall score, the top three TVs in the THX Standard database are the Sony XBR-55X900E LCD, LG 55B7A OLED, and TCL 55P607 LCD. Both LCDs are FALD (full array local dimming).
Among the 2-channel amps, the top three are the Benchmark AHB2, NAD M22, and Cambridge Audio Azur 851W.
For this comparison, I chose the first-, second-, and fourth-rated models, since I was curious to see how the Emotiva XPA-7 Gen3 did compared with the top two: Anthem PVA 7 and Monoprice Monolith 7.
The top three powered studio monitors are the Yamaha HS8, Mackie MR824, and JBL LSR305.
Among the 2.1 PC speaker systems, the top three are the Audioengine A2 S8, PSB Alpha 1-100, and Klipsch ProMedia BT.
I have reached out to THX to learn more about how each individual score is derived. This is especially perplexing when it comes to many of the TV results, in which each individual test includes multiple measurements. I haven’t received an explanation yet, but when I do, I’ll add it to this article.
However, I did learn how the overall score is calculated. In particular, I wondered if some individual scores are weighted more than others in that calculation. For example, how is it that an LCD TV (the Sony 55X900E) beat out an OLED TV (the LG B7a) in the overall score?
According to Peter Vasay, General Manager and Senior VP or THX Labs, “All categories in the TV scoring have equal weight. The Visible Artifact count is not included in the average calculation. Instead, the overall product score is reduced by 5 points for each detrimental visible artifact observed.” Okay, the LG had two observed artifacts, while the Sony had none. If the LG had exhibited no artifacts, its overall score would have been 80, and it would have beaten the Sony LCD.
He went on to say, “Regarding amplifiers, THX considers linearity to be of the utmost importance. So, scores related to distortion are more influential on the final score than other test categories. With speakers, THX considers frequency response to be of the utmost importance. Therefore, the frequency-response test is more influential on the final score than other test categories.”
I am especially interested in the TV testing, which is performed in each set’s movie/cinema mode. No calibration is performed prior to testing. Here are the individual test results for the three top models:
The white point and grayscale are quite good for all three TVs.
The “practical black level” is measured in the black boxes within a 4×4 ANSI checkerboard pattern. Full-screen black level is also measured, as is full-screen white and “practical white” in the context of an ANSI checkerboard in standard dynamic range (SDR) mode. Contrast ratios are calculated from these measurements.
Each set is measured to see how well it tracks SDR gamma (BT.1886). The LG got a lower score than it otherwise would because of errors in the darker section of the curve.
The accuracy of the color gamut is measured at several brightness levels in SDR mode.
The Color and Brightness Accuracy dE measurements reveal how well red, green, and blue track across the SDR brightness range.
Color-saturation tracking shows how accurately each set reproduces different saturation levels of each primary and secondary color in SDR mode.
In HDR mode, this test reveals how well each set reproduces the DCI-P3 gamut at several brightness levels.
Here we see the sets’ RGB color balance and brightness in HDR mode, along with their peak luminance with different sizes of white windows.
Here is an objective representation of screen uniformity. The LG OLED nails it with white uniformity, but the Sony beats it in dark uniformity.
As expected, the OLED TV did much better with off-axis uniformity than either of the LCD TVs.
The results of the visible-artifacts tests are presented in a long list, so I didn’t include that here.
I applaud THX for creating the THX Standard website. With its long-trusted, objective measurements and testing, the site gives consumers the opportunity to see and compare the results of those tests performed on products they are thinking about buying. And it will only get better as more products and product categories are added to the site.
For more, visit www.thxstandard.com.