Car Audio 101
Q: What do I need to hook up my amp? Do I need to buy anything? A: It depends on what you're hooking your amp to. If you're hooking it up to a factory car stereo, you either need a line-out converter to step down the output of the deck to a low-level signal or an amplifier with speaker-level inputs. If you are adding the amp to a system featuring a deck with RCA preouts, all you need for signal transfer is a run of shielded cable with RCA connections. Either way, you will need a heavy-duty power wire (with a fuse or circuit breaker) and a ground wire of the same size. The size of the wire you need depends on the size of the amp you're installing. A great option to simplify matters is to buy a prepackaged amp install kit designed for the size of the amp you want to install. You'll also need some heavy-duty speaker wire to pass the amplified signal to the speakers or subwoofer that you're powering with the amp. Finally, you'll also need a small gauge remote-turn-on wire that leads from your deck's turn-on lead to the amp's remote terminal. This wire will turn your amp on when your radio receives power.
Q: How much power does it take to get good bass from my sub? A: When matching up an amplifier to a subwoofer, it's important to look at continuous power. Many subwoofers and amplifiers are rated at both continuous and peak power; however, continuous power is the best indicator of what your gear can really handle. Try to match the continuous (or RMS) power rating of the sub to an amplifier with a similar continuous (or RMS) power rating. Err on the side of too much power. It is actually better (for the amp and the sub) to have too much amp and run it below its maximum output than to try and push a sub with an amp that is a little underpowered. Using an underpowered amp causes it to clip, which causes distortion that can damage your sub and amp.
Q: I like my factory stereo, but would like to add a CD changer; do I have to go to the dealership? A: Nope, it is fairly easy to add an aftermarket CD changer to any factory stereo (and it's a lot more economical than going to the dealership). Many of our CD changers and new MP3 hard drive devices (like the Kenwood Music Keg) can be hooked up to a simple RF modulator that will broadcast your music via a set FM station on your stereo (usually 89.1). Most of them come with the modulator that you need and a wired remote with display (or sometimes even a wireless remote). Those that do not can be used with an RF mod that you purchase separately. That way you can keep your factory stereo and get mass music storage without a trip to the dealership.
Q: I'm looking at speakers, and their efficiency ratings are only a little different. Does this rating even matter? A: Efficiency is one of the most important specs to look at when you buy a speaker or subwoofer. You want to get the sound that you can, right? Then you want an efficient speaker. For every 3dB of difference, the amount of wattage that you need to play at the same volume doubles. For example, if all other things are equal, a subwoofer with an 89dB efficiency rating needs 200 watts of power to play at the same volume that a subwoofer with an efficiency rating of 91dB with only 100 watts going to it. By choosing an efficient sub, you squeeze every bit of bass possible from your amplifier.
Q: How much power does a factory stereo produce? A: It varies from model to model and trim level to trim level. They are normally much less powerful than their aftermarket cousins, however. Recently, more and more car manufacturers are coming out with upgraded stereo options that make high-wattage claims. What is important to remember is that the ratings displayed are usually a bit... optimistic. The 100 watts that the window sticker brags about probably translates into something like 4 channels of power at 25 watts peak power per channel. This means that the factory system is actually supplying about 10 watts per channel of continuous power (a more usable measurement). That's not bad, but most aftermarket decks provide around 22 watts of continuous power per channel: that's more than twice as much clean power getting to your speakers — delivering improved sound and increased volume. Even if the power difference doesn't matter all that much to you, aftermarket stereos offer a wide variety of advantages also. These include compatibility with aftermarket upgrades like CD changers, amplifiers and high-tech toys like MP3 changers, or mobile video systems and nice features like detachable face security and enhanced displays. They also give you the reliability of a recognized audio brand, which gives you peace of mind.