Given their relatively smaller drivers, soundbars without subwoofers may struggle to reproduce low-frequency sounds. Fortunately, you can elevate your listening experience by connecting an external subwoofer for extra bass.
You can connect an external subwoofer to a soundbar with an RCA cable. Plug one end of the cable into the subwoofer’s line input and the other into the soundbar’s subwoofer output. The subwoofer needs to be ACTIVE if connecting a subwoofer to your soundbar’s PRE-OUT.
Also read: Can You Connect 2 Subwoofers to a Soundbar?
How To Connect a Subwoofer to Your Soundbar
Here is how you can unleash your soundbar’s potential by connecting a subwoofer.
1. Check the Subwoofer Connection on Your Soundbar
The first thing you need to do is determine if you can connect a subwoofer to your soundbar. Not all soundbars have subwoofer outputs, and those that do may have different ports.
Some soundbars may have proprietary outputs which will only work with connectors manufactured by the same brand. However, most output ports work with RCA cables.
You can tell if your soundbar can accommodate a subwoofer by looking at the ports, usually at the back. If the soundbar has ports labeled sub-out or pre-out, you can connect a subwoofer.
Chances are your soundbar has a pre-out since the built-in amp may need to be bigger to drive more powerful speakers.
A sub-out and a pre-out both deliver audio signals, but a sub-out signal is intensified through the built-in amplifier, while a pre-out signal has no amplification.
The sub-out is specifically for passive subwoofers (with no built-in amp) since it filters high-frequency sounds more suitable for other drivers.
On the other hand, a pre-out is a port for external amplifiers, so it will only accommodate an active subwoofer (with a built-in amp).
2. Choose a Suitable Subwoofer
Once you’ve confirmed your soundbar has a sub-out or pre-out, you can choose a suitable subwoofer. If your soundbar has a sub-out, there may be a specific subwoofer from the same brand that can work with it.
Consult your owner’s manual or manufacturer about what subwoofers are compatible with your soundbar.
If your soundbar has a pre-out, you need an active subwoofer unless you’re willing to buy an external amplifier to power a passive one.
A significant benefit of active subwoofers is the assurance that the built-in amplifier is a perfect match for the sub.
Here are some factors to consider when choosing a subwoofer for your soundbar:
- The line-input ports
- Power
- Size
- Frequency response
Most subwoofer line-inputs work with RCA cables. Make sure the port on your soundbar’s output is compatible.
A subwoofer with a power output between 50 to 200 RMS watts should be adequate for most soundbars. You can opt for a subwoofer with more power if your soundbar has a high RMS wattage or if it’s in a large room.
Aside from how much space it’ll occupy, the subwoofer’s size will significantly impact how it sounds. Subwoofers with larger diameters can push more air and usually sound better.
The frequency response of a subwoofer determines how well it can reproduce audible frequencies. Most subwoofers have a frequency response of 20 to 200 Hz.
Think of it this way: Boomy bass that you feel more than you hear are low-frequency sounds, while higher-frequency sounds are sharper and more audible.
3. Connect the Cable to Your Soundbar’s Subwoofer Output
If your soundbar allows a subwoofer connection, you should find an output port, usually at the back of the soundbar.
Output ports transmit audio signals from the soundbar to an external device. Again, a sub-out sends an amplified signal, while a pre-out does not.
Ensure your soundbar is powered off and not connected to a power outlet before working on any wiring.
Plug one end of your audio cable into the output port of your soundbar. Note that RCA cables have a white connector for the left channel and a red connector for the right channel.
The other end of your audio cable is for your subwoofer. Wait until all the wires are connected before turning your soundbar back on.
4. Connect the Cable’s Other End to Your Subwoofer’s Input
Once the audio cable is connected to the soundbar’s output port, you can plug the other end into the input port of your subwoofer. The input port of an active subwoofer is usually in the form of an RCA connector at the back.
Connect the wire for the left and right channels to the correct ports using their designated colors. If you’re using a proprietary connector and cable, you should see a port labeled “subwoofer.”
5. Connect the Subwoofer to a Power Outlet
You can reconnect your soundbar and subwoofer to a power outlet and turn them on after all the cables are plugged in.
Passive subwoofers don’t need a separate power supply since the built-in amplifier of your soundbar powers them. Of course, active subwoofers need that extra bit of power.
6. Find the Right Spot for Your Subwoofer
Where you put your subwoofer will significantly impact how it sounds. For example, placing the subwoofer next to a wall or in the corner of the room can enhance the bass output but also lessens accurate sound reproduction.
To find an ideal spot for your subwoofer, do the subwoofer crawl as follows.
- Place your subwoofer where you’d typically sit while listening.
- Play a bass-heavy track.
- Crawl around the room to see which area the bass sounds the best.
- Mark the spot which gives you the best sound.
- Move your subwoofer where you marked the spot.
If you’re wondering whether you can place your subwoofer at the back of the room, read our other article, “Place a Subwoofer Behind You or in the Back of the Room?“
Final Thoughts
Soundbars are excellent space-savers and can provide decent sound with their small drivers. However, a subwoofer may be necessary to deliver low-frequency sounds that soundbars typically have a hard time reproducing.
Fortunately, many soundbars have output ports that allow you to add a subwoofer for that extra bass.
Jason is a home theater expert with over 10 years of experience in setting up home cinema rooms and systems. What started out as a hobby soon transformed him into an authority in the audio-visual field. He is passionate about providing readers with accurate and up-to-date information on the latest audiovisual technologies and their applications for home theaters. Read more about Jason.