The Los Angeles Police Department has announced the deployment of new technology within its patrol fleet that aims to significantly enhance emergency response times, mitigate traffic incidents and bolster public safety across the city.
The department’s black-and-white vehicles will now incorporate the Federal Signal Rumbler low-frequency warning system.
The innovative system operates in conjunction with existing sirens, emitting distinct low-frequency sound waves designed to be both heard and felt by drivers and pedestrians.
The LAPD stated, “Unlike conventional sirens, these low-frequency tones are capable of penetrating today’s sound-insulated vehicles, allowing drivers to recognize an approaching emergency vehicle sooner and respond more quickly.”
Federal Signal described the sirens as “the ultimate traffic-clearing system,” writing, “Rumbler enhances situational awareness by using a secondary low-frequency tone that penetrates solid materials ensuring vehicle operators and pedestrians don’t just hear the siren, they feel it!”
Additionally, LAPD patrol cars will be outfitted with the Federal Signal Sync Module. This feature enables multiple police vehicles to broadcast synchronized, pre-recorded public safety announcements simultaneously.
Officials highlighted that this capability will empower incident commanders to deliver consistent messages during critical situations such as evacuations, emergencies, or major enforcement operations directly through the patrol vehicle speaker systems.
The department emphasized that this “added level of awareness improves reaction times during emergency responses, helping reduce the likelihood of traffic collisions while enhancing the safety of motorists, pedestrians, and responding officers.”
These technological upgrades were integrated into the vehicles through a redesign by the Motor Transport Division and city vendor partners, incurring no additional cost to taxpayers.


