How to Connect a Subwoofer to a Car Stereo Without an Amp - RRD
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How to Connect a Subwoofer to a Car Stereo Without an Amp

Installing an amp to your car stereo system will boost your listening experience with booming bass. After all, isn’t that what most of us want when we listen to our favorite beats? In most cases when it comes to subwoofers, they have what is called an amplifier which is used to enhance the sound. Normally, we’d suggest you get the best, as is the case with our list of top under seat subwoofers for your car, some of which already have them. However, what if the subwoofer you bought didn’t come with an amp, did you just sink money into a device that is now virtually useless? Rest assured that you can still hook up the subwoofer to your car stereo without an amp.

What You Need

Before we take you through the step-by-step process of how to connect everything, we will give you a list of necessary tools you need before you even start the job. Go down our checklist and make sure you have everything.

  • Tester
  • Spanner and a hammer
  • Screw and pliers

How to Connect a Subwoofer to a Car Stereo Without an Amp – The Steps

Disconnect the Speaker

Your first step is to disconnect the speakers. First disconnect your battery and shut off the infotainment system to avoid accidental shocks. You need to remove the speaker from the dock and gain access to the wiring underneath. Now the next part is to identify the relevant connections.


The next part is quite simple. Connect the LFE (low frequency effects)  jack to the output port of the subwoofer. It might be labeled “subwoofer” or “sub out”. This is for subwoofers only and is usually the only RCA port, which makes it easy to identify. Skip to the last paragraph of step 3 if you have successfully connected your subwoofer.

Other Connections

If you don’t see the LFE output or the subwoofer is missing the input, then try to find the left and right stereo connectors (sometimes labeled as R and L). If the Line In uses cables, then just plug it into the L or R on the subwoofer box. However, if you have two split ends on the cable, then plug it into both the L and R.

Make sure the poles are right, negative with negative and positive with positive. This is when your tester comes in handy for you to test the flow of the electrical current. Just to make sure the crossover and everything is running well.

Enclose the Subwoofer

Once everything is done and the connection is flawless, enclose the subwoofer and place the speaker back in its holding. Now you should be free to enjoy your music with thumping bass!

Just to give you a little bit of extra help to ensure you get the most out of your new stereo system, we’ll introduce the different kinds of subwoofers for you to make an informed decision.

Types of Subwoofers

When asked what kind of subwoofer you want, you’re likely to think you want the “best” one. But what is the “best one”? How does the top 8-inch subwoofers differ from other kinds? The subwoofer you get depends on your car, the type of bass you want, and of course your budget. So let’s take a look at what there is out there.


A powered subwoofer already has built-in amp which saves you time and space. However, the drawback is it may not pack as much power as one with an external amp, such as some of our top picks for 5-channel amplifiers. For those that aren’t looking for precision, powered subwoofers are great.

Subwoofer for Drivers

These are the basic types that come in an enclosure. However, these options need an external amplifier to power it. 

Vehicle Specific Subwoofers

Some subwoofers are even made for your car. This is really helpful if you have a smaller more compact car. They take space saving, into account as well as the budget and the appearance.

How to Pick the Right Subwoofer for Your Car

You know which subwoofer you like and you think it’ll look good sitting in your car, but is it right for your vehicle?

You need to check the enclosures first. Some subs come with an enclosure and some do not. There are two main shapes, with one being more common. Round subwoofers are what you’ll mostly see on the market. However, if you have had a chance to look over some of our best subwoofer lists then you would have seen some square options too! The square counterparts are considered much more durable and better performing. Some models are even compatible for installation to a factory stereo.

The next part is the voice coils. Some are single and some are dual, which offer you more flexibility with wiring. 

The sensitivity rating is also important as that directly affects the power required to operate and thump out the bass.


You don’t necessarily need an amp for your car subwoofer. Sometimes, size is more of an important factor, which you can try out by choosing one from our greatest shallow mount subwoofers list. However, amps help with the sound levels and the bass. If your newfound subwoofer doesn’t come with an amp, it could be tiring to find one that does and you do need a certain know-how to do it. Find one that’s relatively easy to set up to give yourself peace of mind and with the least amount of stress possible. Good luck with your purchase!