The reality is that we are talking about a company, a business, conducting research involving their competitions' products. Think of it like this: would you trust a medical company's research findings, that would indicate that their products are superior to their competitions' products? Especially when no scientifically relevant parts of the study are disclosed?
After all, no matter who conducts the study -- Harman, their competition, or even Feynman -- there are certain reliability and validity issues to consider before making any real assumptions from it (especially sweeping conclusions that "beats sound signature isn't preferred"). That's why methods are usually openly discussed, because there is no 'flawless' method. We wouldn't want any kind of bias going on here, right?
what about the other Harman competitors in the study that people prefer more than Beats?