Code 3’s Tremor™ low-frequency speaker amplifies siren tones as deep low-end sound waves. These low-frequency tones make emergency vehicles more prominently heard at near and far distances, significantly enhancing first responder safety in urban areas and intersections. The Tremor runs in line with the existing siren amp and can be activated via sources such as the vehicle’s horn or the siren’s push button controller for easy activation. Activation intervals range between 7.5 and 60 seconds with automatic shut off. Tremor kits come with an amplifier, two speakers, and two universal brackets.