Component Description: OnStar®: Amplifier
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
Vehicles equipped with Premium Audio (RPO WBM) include an amplifier. The amplifier has low level inputs from the radio for the 4 speaker channels and amplifies the sound. The amplifier receives a radio ON signal from the radio. This signal is delayed momentarily at initial key on to prevent any speaker pops during start-up.
The purpose of an amplifier is to increase the power of a voltage or current signal. The output signal of an amplifier may consist of the same frequencies as the input signal or it may consist of only a portion of the frequencies of the input signal, as in the case of a subwoofer or a mid-range amplifier.