How To Hook Up Your Car Subwoofer To A Home Stereo - A Step-By-Step Guide

Are you thinking about putting that one extra car subwoofer to good use? Why not hook it up to a home stereo!

Connecting a car sub to your home stereo is not a bad idea at all - it’s a great way to get better sound quality on your home system.

However, it’s not a simple process; you have to follow a few steps to get it done. Don’t let this discourage you as it is totally doable, and the steps are pretty straightforward - or at least will be, after you peruse this guide on how to hook up your car subwoofer to a home stereo. 

Roll up your sleeves, and let’s get straight to it!

Can you hook up a car subwoofer to a home stereo?

Well, the quick answer would be - it depends. 

For one thing, you wouldn’t be here reading this guide if it weren’t possible. That being said, there are a few restrictions when it comes to hooking up a car sub to a home stereo. 

Before you try to do it, you have to grasp a few basic things first. And don’t just glance at this part, as it’s pretty vital unless you want to damage your home receiver or amplifier. 

Here’s the gist - you can hook it up directly if:

• Your home stereo or amplifier can handle 4-ohm speakers. This is not likely to be true, but for the sake of thoroughly answering the question, it has to be stated.
• You use workarounds - a small 4-ohm amp between the receiver and sub. 
• You have a subwoofer(s) that can be wired for 8 ohms total. More precisely, they can be wired for 8 ohms total AT LEAST. It can be two 4 ohm subwoofers or one 4 ohm DVC (dual voice coil) subwoofer:

If you’re wondering - “Why can’t I use a 4 or 2-ohm car sub with a home stereo?” 

Here’s why:

The biggest obstacle you’ll encounter here is that most home stereos and home amplifiers cannot handle the 4-ohm speaker load of car subs. 

Just like car stereos and car amplifiers, home stereos also feature a minimum speaker load (expressed in ohms) that they can handle.

You have to avoid connecting a speaker with an impedance that’s too low for your home stereo amp or receiver. Doing so can result in overheating and potential long-term damage to your appliance as it will try to produce more electrical current than it’s designed to. 

Why is matching speaker impedance so important?

You want to match the impedance - not go above, and certainly not go below. 

As you can see from the diagram, if your speaker is over the rated ohm spec, it will work (safely), BUT you sacrifice the quality of delivered power and the volume. 

This is not as bad as going below the rated ohm load. That is quite dangerous, and IT WON’T WORK.

Subwoofer passive speaker crossover

Another thing you’ll likely need but have possibly overlooked is utilizing a speaker crossover for clear bass. 

When you use a car subwoofer in the car as intended, you don’t have to think about this, as car subs are typically used with a car amplifier that has a built-in low-pass crossover. 

Albeit sometimes they have a subwoofer RCA output jack, oftentimes, this is not the case with home stereos. 

It boils down to this: If you want clear bass, you’ll have to hook up a subwoofer speaker crossover between the sub and the stereo in order to block high-frequency sounds that subwoofers can’t play well. 

That is if you’re not so lucky as to already possess a receiver or a home amp with a built-in low-pass crossover.

If not, you’ll want to hook one up. Otherwise, you risk hearing vocals and other sounds from the car subwoofer that you probably don’t want to hear. 

How to connect a car subwoofer to a home stereo

Does the total ohms load meet the requirements? Great! Now you can begin to hook up your car subwoofer to your home stereo. 

Here are the essential steps - just stick to them, and the whole process should be a piece of cake. 

Step #1 - Control the power

So, here’s the thing. One of the concerns with this DIY hooking up project is frying your subwoofer by running it on 110 volts when it’s made to run on 12 volts generated by your car’s battery. 

This means you’ll need to get a power inverter that will allow you to control the power. You should get an inverter that’s capable of converting 12 volts and has two plugs - one for the woofer and one for the wall outlet. 

Did you already get your hands on a power inverter? You can skip to step number two and have a little patience, as plugging is actually the last step. 

Step #2 - Connect the car subwoofer to the car amplifier

The next step includes taking a twelve or sixteen-gauge speaker wire. This one depends on the model of your car subwoofer, so make sure to check the specifications and use the right one. 

You’ll have to connect the subwoofer and amplifier to the wires. The wires connect to the brackets underneath the terminals of the appliances. 

Don’t forget that red wires must be twisted with red wires, and the dark ones must be twisted with dark wires (you might need to strip the wires first).

Step #3 - Connect the car subwoofer to the home amplifier

You will need to pair red wires with red wires and white wires with white wires for this next step. This step requires you to connect the wires to the input terminals of the car’s audio subwoofer before you connect it to the output terminals of your home amp. 

Step #4 - Connect your other speakers

It’s time to connect the remaining speakers in the home system. For an extremely powerful surround sound experience, put two speakers on your left, two on your right, and one in the center. 

If possible, make use of the RCA wires to connect these to the main amp.

Step #5 - Plug in the power inverter

It’s time for plugging! As mentioned in the first step, the last step is usually plugging. 

You need to plug the subwoofer into the power inverter and then connect the inverter to the outlet on your wall. 

Now, play some music and enjoy the sound. 

FAQ

Q: Are there any disadvantages to using a car subwoofer at home?

A: The idea of hooking up your car subwoofer to your home stereo really does sound intriguing, but is this little DIY project without flaws? Certainly not. 

Namely, there are a couple of things to keep in mind as the possible downsides of doing this. 

The first thing is that if you make a mistake, there could be serious consequences. For instance, if you do something wrong, you risk blowing your entire equipment. As mentioned earlier, a mistake could lead to overheating and permanent damage, so don’t take this warning lightly. 

If it comes to it, don’t sweat it - peruse this helpful guide on how to fix a blown subwoofer. It’s beginner-friendly!

The second downside is that you have to cough up a certain amount of money to perform this successfully. 

When you add up all the expenses, this adventure could end up costing almost as much as fairly used home subwoofers. 

Q: Will a subwoofer work without an amp?

A: The answer to this one is pretty straightforward - no, the sub won’t work without an amp. Or, to rephrase it, it won’t work properly. You need an amplified speaker output in order for it to sound and work alright. 

Q: What if my receiver doesn’t have a subwoofer or other RCA outputs?

A: In this case, you can use a line-level converter. They are typically used for factory-installed car stereos. 

Make sure to use a high-quality one that has adjustable output level dials, so you don’t encounter a problem with signal levels.

A few options for line-level converters to use in order to get an RCA low-level signal from a home stereo that doesn’t have subwoofer RCA outputs: