KNOXVILLE, Tenn. (WATE) — You may start spotting noise cameras when you’re driving around Knoxville. The city said it’s planning to test the new device. They’re sort of like a red light camera – but triggered by sound, mainly from loud cars.

WATE 6 On Your Side’s Elizabeth Kuebel talked to the company behind the camera, Intelligent Instruments Ltd, which is based in the UK. The company has 7 permanent systems in London and within the U.S., New York City is doing a trial run. It’s the only place using the cameras within the U.S. right now. However, Knoxville is also planning its own trial.

“The noise camera system is a class 1 precision sound level meter at the heart of it. With a couple of high resolution cameras attached to it. It’s measuring video and audio and noise levels all the time. It’s waiting for a noisy vehicle, and when it detects one, it captures video, audio, noise levels, and uploads everything to a web server, where someone can review it and make a judgment as to whether it’s ok or not,” said Intelligent Instruments director, Dave Coles.

Coles said they are in the process of getting a trial system shipped to Knoxville.

“Cars, performance cars with modified exhaust and also motorbikes with illegal exhaust,” that’s what Coles said the noise cameras pick up on.

What they don’t pick up on, he said, are conversations, despite how loud they may be.

“A, because a voice wouldn’t really be loud enough. And B, because it’s not generating at the frequencies that we’d be looking for,” said Coles.

The device is constantly recording, he says, but also constantly deleting.

“It’s continually recording, but then deleting data that’s a few seconds old. But as soon as it detects something, it will keep the last few seconds plus the next few seconds,” said Coles. “We’re looking at frequencies that are specific to car exhaust or vehicle exhaust, and anything else is pretty much ignored.”

The typical cost per unit is $25,000. The City will be placing signage downtown announcing the use of the enforcement technology. A spokesperson said they do not have a demo date right now.