Car Amplifier Shopping Guide

Why add an amplifier?

If you want your music to be loud, amplifiers are definitely part of the picture. But whether you run your system wide open or softly enough for conversation, a power amplifier will breathe life into your music, bringing out all of its excitement and detail. Here are a couple of the main benefits of adding an amp:

• Better sound quality — Adding an amplifier gives you a clean power source that can drive your speakers without straining. Unlike an amplifier built into an in-dash stereo, an external power amp isn't limited by the space available — it can be designed without compromises. That means your music will sound cleaner and more defined at all volume levels.
• Power for upgraded speakers — A factory system or an in-dash receiver may not do justice to your upgraded speakers. If you're adding high-quality aftermarket speakers or component systems to your vehicle, they may require more power for peak performance than your existing in-dash receiver can provide.
• Powering a subwoofer — Subwoofers require significantly more power than a brand-name or factory in-dash receiver can provide. A separate amp is a necessity.

What kind of speakers are you going to power?

Most amplifiers, like this Rockford Fosgate R400-4D, also give you the controls you need to shape that power to best suit your speakers.

• Subwoofers — A mono amplifier makes a great choice for powering subwoofers. They're specifically designed for low-frequency reproduction, with built-in bass boost and low-pass filters. Class D mono amps are often a good choice — they draw less current, produce less heat, and are more efficient than conventional amp designs. [Shop for mono amplifiers.]
  
  You can use a 2-channel amp for powering two subs, or bridge the amp to single channel operation for a single woofer. Likewise, a 4-channel amp can be bridged to 2-channel mode to power a pair of subs. How much power you need depends on the subwoofer(s) you'll be using, but figure on at least 150-200 watts per sub for 10" or 12" subwoofers. [Shop for 2-channel amplifiers.]
• Full-range or component speaker systems — Use a 2- or 4-channel amplifier for this job, depending on the number of speakers you want to power. Be sure the amp has high-pass filters. [Shop for 4-channel amplifiers.]
• A combination of full-range speakers and subwoofers — A 4-, 5-, or 6-channel amplifier fills the bill here. In the case of a 4-channel amp, use two channels to drive a pair of full-range speakers, and bridge the other 2 channels to power a sub. 5- or 6-channel amps give you even more options. You can also use a 2-channel amplifier with a tri-way crossover to power a set of speakers and a sub. [Shop for 5-channel amplifiers.]

Will I have any trouble connecting an amp to my existing system?

No. Amplifiers can be added to almost any car stereo, whether it's factory-installed or an aftermarket receiver. An amplifier accepts the signal from an aftermarket receiver through its preamp inputs. If you're tapping into a factory system, look for an amp with speaker level inputs. This allows you to tap into your vehicle's existing speaker wiring without special adapters. If you're planning a multi-amp system, preamp outputs simplify the wiring setup. [Shop for amplifiers with speaker-level inputs.]

How powerful an amp do I need?

Choose an amplifier whose power output is rated at least 75% to 150% of the power handling of the speakers you'll be amplifying. Make sure you're comparing the RMS power ratings of both the amp and speakers. And remember — it's better to overpower your speakers a little than to send them too little power.

Need more help?

Browse our selection of car amplifiers. If you need more help, give our Advisors a call at 1-888-955-6000. They have the knowledge and experience to help you find an amp that will meet your needs.