If you have the best speakers you can afford, it’s natural to want the best bass response from your audio setup. You’ll need to learn how to connect a subwoofer to speakers. A good subwoofer will provide deeper reproduction of bass and sub-bass frequencies, but it has to be connected to your speakers properly to get peak performance without damaging either the subwoofer or your speakers.
Overall, it isn’t a difficult task, but you need to know the proper steps before you go about it, so keep reading. While you’re at it, look into how to connect speakers to a receiver. You may also want to read about how to connect to multiple Bluetooth speakers and how to tap into rear speakers for subs.
A subwoofer is a speaker designed for low-frequency audio reproduction. If you are looking to add that thumping sub-bass sound to your audio setup or aren’t satisfied with the low-end performance of your regular speakers, adding a subwoofer is your answer.
A subwoofer isn’t generally connected to your receiver, especially if it’s an older receiver that lacks direct subwoofer outputs. You have to connect and sync up to your standard stereo speakers. Newer digital audio tech, like the Sceptre SB301524W smart speaker soundbar 2.1 with built-in subwoofer and android platform, may have a different connection design. Still, these instructions will apply to most situations.
Using a speaker-level connection will usually make it easier to dial in the clearest audio possible using the subwoofer’s filter.
There are two main connection types used to connect a sub to speakers: low-level and high-level. A Low-level connection is also called an LFE, a .1, or a line-level connection. This can be a TRS (1/4″), XLR, or even an RCA connection. A High-level connection, also known as a speaker-level connection, uses speaker wire instead of audio cables.
Take a look at your receiver’s input, output, and other specifications to determine your options for connecting your speakers and subwoofers.
Determine your subwoofer’s input and output options. You’re looking to see if the preferred connection option is available. This will usually be via speaker wire. Most subwoofers will have an input/output port on the front and back, but not all do. Double-check both the receiver and subwoofer’s specs before proceeding.
If the connection type is an LFE, run the two TRS or RCA cables from the left and right LFE outputs on your speakers to the matching inputs on your subwoofer.
If the connection type is a high-level connection, make sure your receiver is powered down and run the speaker wire from the right and left speaker to the sub’s speaker wire inputs.
Power on your receiver with the volume all the way down, then turn the volume up to mid-level. If you hear a loud hum, you may have a ground issue. Check to be sure all your cables are in good condition without any obvious damage and that all your inputs and outputs are free of dirt or dust. If you’re still hearing hum, you may want to connect your receiver to a power strip with a ground switch. Switch the ground switch on and off to see which position removes the hum.
Adjust your subwoofer’s filter while playing music at mid-level volume until the audio is clear and free of “mud” or distortion. You may want to mark down the filter position for future reference.
Always make sure your receiver (and speakers if they’re powered) is powered off whenever connecting your subwoofer.
Enjoy that improved bass response!
STAT: The first home audio subwoofers were introduced in the 1960s. (source)
Why connect my subwoofer to speaker-level outputs?
Connecting your subwoofer via speaker-level outputs as opposed to LFE or low-level connection outputs will typically make it easier to get a clear, clean sound without “mud” but plenty of thumpy sub-bass using your subwoofer’s filter.
Can I connect both the High-level and Low-level connections simultaneously?
Sometimes this is possible, but you need to carefully check the specifications of your receiver and subwoofer before attempting it. Even if both connection types are possible, manufacturers will often recommend using only one.
What’s a line-level converter?
Line level converters take speaker wire from High-level connections and scale down the level’s signal to a low-level signal (usually an RCA jack). These are most often used in car stereos where LFE connections need to be used, but there are no RCA outputs available.