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Video: Infinity Reference car amplifiers

Improve the sound of your factory stereo or aftermarket system

Heads up!

Welcome to this article from the Crutchfield archives. Have fun reading it, but be aware that the information may be outdated and links may be broken.

Infinity Reference car amplifiers are a great way to add power to your car audio system, even if you want to keep your factory stereo. There three amps in the line, a mono sub amp, a 4-channel amp, and a 5-channel amp that can power your whole system. Check them out and contact our advisors if you have any questions. 

Read video transcript

Hey, I'm JR, and I'm here today with the Infinity Reference line of amplifiers. There's three amps in the line, there's the mono sub amp, the 551A, the 4-channel amp, the 704A, and the 5-channel amp, the 455A. They're all Class-D amplifiers, which means they're efficient. They're smaller in size, so they can fit where you want them. They don't create as much heat, and they do a really nice job of turning your car's electricity into music.

They also are all fine to hook up to an aftermarket radio using the preamp inputs, and a factory radio with speaker-level inputs, and technically they're the same inputs on this amplifier. The RCA inputs can handle low-level signal from your aftermarket radio or speaker-level signal from your factory radio. They even come with an adapter so you can take your factory speaker wire in this side, RCA right into the amplifier on that side. This adapter is separate with a lot of other amplifiers. It's like that with all of these amps, it's kind of a nice little touch.

The 551a is the mono sub amp. At 4 ohms of impedance it's gonna put out about 370 watts. However, if you can get a 2 ohm sub or wire your voice coils down to 2 ohms, you're gonna get a full 550 watts out of that mono sub amplifier. It's a nice small simple box of power that will make your sub sound great.

The 4-channel amp is about 70 watts by 4, and it adds a convenience feature in addition to those inputs. It's also got a set of preamp outputs, so if you want to daisy-chain it with the subwoofer amplifier, it's nice to be able to do that without having to run another RCA cable all the way up to your factory radio or your aftermarket radio.

It's also great for integrating with your factory radio, especially if your car has the ADAS system, advanced driver assistance system. That's where it gives you like alerts and stuff on your speakers when you're going to run into things. It's got an input specifically for that, so that you can get those alerts on your speakers even if you replace the amplifier.

And it's also compatible with HALOsonic. If your car has HALOsonic, then you probably know it has some noise cancellation to reduce road noise and wind noise, it can also create noise if you have like a hybrid or an electric vehicle where you want more noise than you're getting out of those super quiet cars. It's compatible with those systems as well.

So is the five-channel amplifier, the 455a, fully compatible with ADAS and HALOsonic, so it's fully ready to go for factory integration. And it's five channels of power, so it's a 45-watt by 4 4-channel amplifier, and a 500-watt by one subwoofer amplifier. Now you can take those 4 channels if you want and bridge them to 2, which means you're gonna get about 130 watts to your front speakers. This makes sense if you've got a really nice set of front speakers, maybe some components with separate tweeters, and you want to give them a lot of power. You can do that by bridging the four channels to 130 watts to those front speakers, and let the sub channel take care of the bass.

Long story short, it's a simple, great line of amplifiers. There's three amplifiers, so you got pretty much what you need from Infinity for any speakers you want to put in your car. And of course, adding an amp is critical if you want great sound. So if you have any questions on the Infinity line of amps or anything else, give us a call, chat with us online, or send us an email, we can help you get the right amp for you.