Officer Craig Sroka has decades of local service under his belt. He often shares questions his 300,000 followers ask about his work with the Coventry, Rhode Island, police department. After getting back from a family trip to Disney World, the Rhode Island native logged on to explain the “rumbler.”

A rumbler is a low-frequency siren system used on some police cruisers

It doesn’t replace the regular siren – it works alongside it. Think of it as the bass drop in a techno remix of your standard “WEE-OO-WEE-OO.” The rumbler emits deep, pulsing tones that literally shake nearby vehicles and objects. So even if your windows are up, your stereo’s blasting, and your attention is on everything but the road, you’ll still feel the cruiser coming.

Officer Sroka explains that the rumbler works well if the general driving public is “numb” to siren sounds. He started the video talking about why police cruisers have different sirens for different codes.

From the officer’s point of view, the rumbler is a manual tool. It’s usually controlled by a button or switch on the console. They don’t leave it on all the time – it’s more of a tactical option. 

An officer might hit it when traffic isn’t clearing, or when they’re approaching an intersection where people clearly aren’t paying attention

The idea is to give drivers an unmistakable physical cue that something urgent is bearing down on them. The shake is hard to ignore.

Mechanically, it taps into the existing siren tones – usually the wail or yelp – and adds a bassy overlay. That low-frequency blast is what creates the vibration. It runs for short bursts, usually no more than ten seconds at a time. After that, it either auto-disengages or has to be manually shut off, depending on the system installed.

You’re most likely to notice it when a cruiser is close, sirens are going, and for some reason, no one’s moving. That’s when the officer says, “Alright, time to wake ’em up,” and hits the rumbler. You might not hear it first, but you’ll definitely feel it.