Ans: In general, a 5-Channel amplifier is used to connect up to 4 – speakers (front – left/right, rear – left/right) and 1 subwoofer. Simply, this amp boosts the power of the entire car audio system to effectively run the system that includes two front and two rear speakers along with a subwoofer. Some models are bridgeable which lets you combine two channels to boost the power and accommodate various setups.