The Brief The LAPD is deploying new black-and-white patrol vehicles equipped with low-frequency sirens and synchronized announcement speakers. The "Rumbler" system uses low-frequency sound waves that drivers can physically feel through noise-insulated cars, while a sync module lets multiple police cars broadcast unified public safety announcements at no extra taxpayer cost. The Los Angeles Police Department has begun deploying redesigned patrol vehicles equipped with low-frequency siren technology and synchronized loudspeaker systems. In addition, the vehicles are fitted with a Federal Signal Sync Module that enables multiple patrol cars to simultaneously broadcast synchronized, pre-recorded public safety announcements. What's next:The LAPD will continue rolling out the newly equipped black-and-whites across its fleet as redesigned patrol units are deployed to active duty.