The Celebrity Quality Control Knob (CQCK) is a device first introduced in 2014 by German TV channel SAT 1 during an advertisment for its then-upcoming reality show, Promi Big Brother.

Plagued by the lackluster reputation of the Big Brother franchise, producers of the show apparently responded by turning to previously untested, sci-fi-inspired, borderline supervillainesque high technology. The inventor of the CQCK is as of yet unknown, and there have been speculations that producers of the TV show, and several representatives of the Pro7Sat1 Media AG, have fallen victim to a scam. Yet, as will be pointed out, there exist other possible explanations for the failure of Promi Big Brother to come up with higher level celebrities.

While the Celebrity Quality Control Knob's screen time didn't add up to more than a fraction of a 60-second spot, the available footage heavily implied that the device was supposed to increase celebrity quality drastically. During the 3-second segment where the knob is visible, the full range of its capacity is utilized, with an invisible hand turning (colloquially: "cranking up") the knob from the lowest level, "D", to "A", the highest level. As the spot progresses, it is furtherer implied that the tuning of the knob triggered a mechanism that caused a number of people at various locations to be sucked into a giant vacuum tube that directly transported said persons to the Big Brother house.

At this point it is important to note that even the most basic assumptions regarding the CQCK's workings are highly speculative, since the TV spot offered little explanation, and Pro7Sat1 Media seems unwilling to release any conclusive information on the device. Some experts have suggested that a basic misunderstanding of the CQCK's function might be in place, as the enhancement of Big Brother contestants' celebrity status might occur a posteriori. The majority of people in the field however described this idea of fame increasing through Big Brother as "absurd". Others have argued that the CQCK's mechanism may largely be a suggestive one, working for viewers in a way similar to a placebo. Illustrating this phenomenon, a media professional was heard quoting Lin Yutang: "Hope is like a road in the country, there was never a road, but when many people walk on it, the road comes into existence".