Adding a 4 channel amp is a great idea. Very nice! It means 2 channels are sharing the workload of one speaker between them and therefore and drive it with more power. A 4 channel car amp is basically an expanded version of a 2-channel amp. This saves installation space and makes it easier too. Whether you have a factory stereo or a great aftermarket non-factory one, adding an amplifier is one of the best decisions you can make.
Almost all home theater receivers or processors and some stereo receivers have this type of subwoofer output. It's usually just one cable with single RCA connectors on both ends. Sometimes you'll find that a receiver or amplifier does not have the LFE subwoofer output. Or it might be that the subwoofer doesn't have the LFE input.
Using an amplifier with new speakers is an absolute must if you want to get the most out of your sound system. Thankfully, upgrading your speakers and amplifier is a pretty straightforward process and you can save a lot of money installing the parts yourself. The basic stereo system your car comes with is not that great when it comes to delivering quality, power, and volume.
Amps are the acronym for amplifiers. Amplifiers are electronic devices that are used in the process of increasing the amplitude of electrical signals. Sound reproduction is the process where the amplifiers are used the most. In simple words, an amplifier is a device used to increase the volume of any electrical, musical or sound emanating instruments.