Maybe you already have a high powered sound system or maybe you’re considering adding one. You want to get the most out of your amplifiers, right? You want your sound system to be totally optimized and sound the best it can, right? Wouldn’t you like to be able to get every Watt, every bit of clean, undistorted power that your amplifier was capable of producing? Optimizing the way your audio system sounds starts with making sure each piece of equipment is getting what it needs.
» Read more: Optimizing Your System – Do You Have Enough Power?
These days, adding an amplifier to an OEM head unit does not require an investment of vast amounts of money. With newer vehicles or vehicles with factory “amplified” sound systems things do get a little more complicated on occasion. The main things that factory systems lack are power and the ability to reproduce the lower end of the musical spectrum. 
The first step in system design or building with amplifiers is to determine your needs. If for instance you are only planning to add amplification to your factory speakers or “basic” upgrade, then a small inexpensive amp will do. If on the other hand, you have bigger expectations than you may need a number of multi-channel amplifiers.