Video: car amplifier features
What to look for when buying an amp
This short video describes some of the common features you should look for when you're shopping for an amplifier for your car audio system. Not every amplifier will have all of these features, so make sure the amp that you get has the ones you need.
Read video transcript
Zak: Depending on the kind of amp you're getting and how you're going to use it, there are some features built into most amps that you should think about while you're shopping.
Ken: These can include high- and low- pass filters, bass boost, and speaker-level inputs. High-and low-pass filters have an important job to do. They make sure that your amp is only boosting the frequencies that you want it to. High-pass filters strip away the low frequencies from the signal the amp is boosting. You'll use the high-pass filter when the amp is powering smaller speakers like those in the front doors of your car. This way your amp will direct its energy to making the vocals and instrumentals sound their best.
Zak: Low-pass filters do just the opposite. They take out the highs so you're only amplifying the lows. You'll want a low-pass filter when you're using the amp for powering a sub, that way the amp can concentrate its power on kicking out the low notes.
Ken: We should mention one other type of filter, the subsonic filter. A subsonic filter blocks ultra low frequencies that you can't hear from getting to the subwoofer. This lets the sub operate more efficiently.
Zak: Yeah and there's a couple other important things to look for in your filters. Some filters are variable. They let you select the frequency for the filter. Others are fixed, meaning that they limit you to a specific frequency.
Ken: Variable filters let you tailor the output of your amplifier more precisely than you can with a fixed high-or low-pass filter. And there's one other feature to look for: a bass boost.
Zak: Yeah, a bass boost augments the low frequency output of the amp so you get a bigger bass output with your subs and your larger speakers.
Ken: A bass boost frequency can be fixed or variable and the amount of boost can be fixed or variable too.
Zak: Yeah kind of like the filters we talked about. Variable bass boosts give you some more choices in how you tailor the sound that your amp puts out so keep an eye out for this feature if you're planning to amp subs. Now besides the number of speaker output channels we talked about earlier, amplifiers have other outputs and inputs that you may want to look for.
Ken: The first is speaker-level inputs. Most amps get their signal from the receiver through RCA inputs which are connected to your stereo's preamp outputs. The factory radios rarely have preamp outputs so if you're connecting your amp to a factory radio the amp will need speaker-level inputs like these. They'll let you tap into your car's speaker wires for the signal your amp requires.
Zak: If you're going to put together a system with multiple amps, you might want to think about an amp like this one. The reason is it has preamp outputs so you can send a signal into the amp and then out again and into another amp without having to run any extra cables all the way from the stereo.
Ken: To see all the amps we carry go to crutchfield.com/amps and be sure to check out which wiring kits we recommend.
Zak: To learn more about choosing the right amplifier, go to crutchfield.com/ampguide.
Ken: And for personal one-on-one help, call 1-800-555-9408.
by Crutchfield's
Meet Ken Nail
My name is Ken. I seek the Holy Grail of car audio excellence. My favorite color is blue.
I came to Crutchfield in 1999. During my six years as a Crutchfield Advisor, I learned a lot about the technology behind great car and home audio. I learned even more about what people wanted in their car stereo systems.
I've been a writer for car audio and fitness tech at Crutchfield since 2005. Over the last few years, I've also carved out a niche producing demo videos for our in-dash car stereos. The hands-on experience I get with car stereos while doing video production is an invaluable aid to me in learning about their exciting features. This helps me convey that information to our customers when I write about the stereo on our website.
Before coming to Crutchfield, I spent 10 years teaching music in Charlottesville area schools. I keep my musical interests satisfied by volunteering as a classical music DJ at a local community radio station, and I stay up to date with the latest in outdoor tech by cycling, running, and backpacking.
Fun facts: I've completed an Ironman triathlon, run the Boston Marathon, hiked 1150 miles of the Appalachian Trail, and lost on Jeopardy!
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Meet Zak Billmeier
I'll do my best to make videos that are helpful and interesting.
I've been a camera nut since I was a kid. I got really into it around age 12, when I got hold of a Pentax K1000 35mm camera. My father is a photo nut also, and we had access to a darkroom. Ever since then I have delighted in trying out new cameras, lenses, and photo techniques. Working here at Crutchfield, I get to handle all the new and cool camera gear I can get my hands on.
I'm also into audio, from car audio to home audio to headphones. I'm a music lover, and an eye-opening moment for me was discovering just how much more there is to musical recordings when you listen using high-quality gear. It's an experience I try to pass along to others as often as possible. I truly believe that having good quality gear in your car or home can really enrich your life.
I started getting into the video side of things early on in my Crutchfield career while I was a copywriter for car audio products. In those days our video program was just getting started, and many of us pitched in when our writing and editing duties allowed. Today, we have a dedicated team that makes hundreds of videos a year, including spotlights on products and product lines, how-to videos, videos that shine a light on our company, end everything in between. I am proud to be a part of that team and of the work we do.
My job is a lot of fun because I get to play around with all the cool stuff you see on our website while I'm making videos. Getting hands-on with the gear helps me see what I should show you about a product, and I look at our videos as a way of having a conversation with you when you are considering a purchase. If I do my job well, you should come away from a Crutchfield video understanding why you do — or don't — want that product. In the end, it's gotta be something you enjoy.
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