Your subwoofer sounded just fine before it became quiet, but now it’s beating so faintly that you can’t even tell it’s in the room, especially at deep bass frequencies. You haven’t changed any settings or replaced the unit.
So, you may wonder what to do to rectify the nerve-racking trouble.
Here’s what you can do if you can barely hear your subwoofer:
- Ensure you’re playing low frequencies.
- Bring up the woofer level.
- Modify sub crossover.
- Ensure your subs are in-phase.
- Provide sufficient power to your sub.
- Alter the equalization settings.
- Manage the bass.
- Improve room acoustics.
- Move the subwoofer to another place.
- Tweak receiver settings.
This article will talk about why a subwoofer stops punching out of the blue and how you can pinpoint and solve the issue. Here are ten practical fixes to regain your subwoofer’s bass notes:
1. Ensure You’re Playing Low Frequencies
Subwoofers are dedicated speakers to output low acoustic frequencies. So, it’s plain as day that you can’t hear anything if no such frequencies exist.
Play something that you know has strong bass like kick drums, pipe organs, or any other sound effect with 30 to 200 Hz frequencies. Then check if the issue persists.
2. Bring Up the Woofer Level
As ridiculous as it seems, sometimes barely hearing your subwoofer is because your woofer volume remains at the minimum level. Since subwoofers have an exclusive volume controller than other woofers, you likely forget about it.
So, grab your soundbar remote and press the “Woofer” switch to up the volume. If you can’t locate the button, consult the device booklet to find a way.
3. Modify Sub Crossover
Crossover is a certain frequency point where your subwoofer starts reproducing audio. And since every speaker has its own tolerance range, you should adjust the crossover to a frequency that it can properly handle.
A typical subwoofer has a crossover point of 80Hz, so for starters, you can set it to this value and check if the issue disappears. If it doesn’t, check your product manual to find out its crossover point.
4. Ensure Your Subs Are In-Phase
When you have more than one sub in the same enclosure, there’s a chance of phase cancellation. It happens when you wire the positive and negative sides of one of the woofers interchangeably.
If you connect both woofers’ positive ends to the positive end of the amp—and likewise, wire their negative terminals to the negative port of the amp—both of them receive audio signals from the negative side and reproduce them on the positive side.
However, if you wire one of the subs conversely, it starts working in the opposite direction. (If your subs were human, it would be like pushing the same object from opposite sides: It wouldn’t move, would it?)
We call this phase cancellation or the out-of-phase problem.
To rectify it, check the back of the units and ensure the wires are correctly in place.
5. Provide Sufficient Power to Your Sub
When you provide insufficient power to your subwoofer, say, 300 W less than its required RMS, it won’t have enough fuel to deal with all the audio signals.
As a result, it starts clipping some of them to match the signal load to its capacity. (Think of an overloaded trunk that wants to pass through a very short tunnel. To do so, it has no choice but to cut off a part of cargo).
When this happens, you’ll hear a distorted, muddy sound with less punchy bass.
So, ensure you haven’t underpowered the sub. As a rule of thumb, use amps with bigger RMS. For example, if you have a 200W subwoofer, a 250W amp will do the trick.
6. Alter the Equalization Settings
The equalization settings let you modify the volume of different frequencies—isolating, boosting, diminishing them.
So if you’re still barely hearing your subwoofer, get to that setting.
If you’re listening to sub-bass and kick drums, set it anywhere between 20-60 Hz. But for something like guitar, bassoon, tenor saxophones, and cello, keep the EQ controls between 60-200 Hz. Most modern music tracks fall into this category.
7. Manage the Bass
Aka bass redirection, bass management lets you decide which frequencies go to which speaker. So, by adjusting it, you can direct all the bass frequencies to the subwoofer and rectify the woofer’s low volume.
Here are a few settings you can adjust:
- Phase Control: Also called polarity switch, it’s the rotative knob at the back of your subwoofer that lets you add electrical delay to the receiving audio signals. It helps your subwoofer interact better with other speakers and also prevents phase cancellation. Play around with your phase switch to see which value delivers the best results. While adjustable between 0 to 180 degrees, the 120-degree position is usually the best setting.
- Low-Frequency Effect (LFE): LFE channel is an option in the Subwoofer Mode menu that yields bass-only signals. When you set your subwoofer to this track, it’ll access deeper low ends—less than 120 Hz—that may not be audible from other channels (it may also be labeled as the 5.1 or 7.1 audio track)
- LFE+Mains: This channel sends duplicate acoustic data to your woofer, no matter if you’ve set it to Small or Large/Full Range settings.
8. Improve Room Acoustics
Room acoustics is about how the sound waves propagate in a room in response to the reflective or absorptive properties of the objects.
It means that whatever you hear from a speaker isn’t just a product of your audio system but a mirroring effect of all the existing walls, furniture, etc. This is especially true about subwoofers since low frequencies are more sensitive to other surfaces.
Poor acoustics can affect your subwoofer in two ways: standing waves and nulls. Nulls can make the sound signals very weak to the point of inaudible. And standing waves flutter the echoes due to interference between existing frequencies, especially in a studio.
But whatever the case, you have to improve your room acoustics to ensure the issue doesn’t lie within the audio system.
The first and easiest option is to buy or build DIY bass traps. But if you don’t want to break the bank, start by putting some sound-absorption objects such as a flower pot, bookcase, etc., in the area. And remove glass furniture or long parallel surfaces.
9. Move the Subwoofer to Another Place
Other than room modes, your speaker’s position and distance from walls can also affect their sound quality, especially if your sub is ported.
To improve the woofer’s placement, first put it closer to the source. Place in the corners to avoid distortion from parallel walls. And make sure it’s
Keep it at least a few inches far from the wall—typically, twice the thickness of the open port.
While testing the different positions, move around the room to ensure your standing status isn’t affecting your listening experience (standing at the center of the room isn’t ideal for judging a speaker’s sound).
You would also want to distance it from interfering Wi-Fi or Bluetooth devices.
10. Tweak Receiver Settings
If altering the speaker doesn’t rectify your sub volume issue, try modifying the receiver. Here are a few tips:
- Sub Output and Sub Volume: Other than the speakers themselves, your audio/video receiver also has some settings to adjust the subwoofer. One of them is Sub Volume and Sub Output. Navigate these options through the receiver’s main menu, and set them to the maximum value.
- Bass Enhancer: It’s a useful feature that sometimes adversely affects your subs. So, switch it off to see if the volume changes.
Stereo Mode: When set in 2.0 channel config, your receiver may not recognize your subwoofer and don’t send any signals to it. So, you need to switch to the stereo mode or 2.1 channel mode.
- Speaker Size Settings: Some speakers let you adjust them to larger size settings. But when you do this, they may try to take over all the frequencies, even the low ones that should be in control of the sub. As a result, your sub won’t pick up any signals, failing to play appropriately. So, go to your speaker’s main menu, and set the “Speaker Size” option to “Small.”
A subwoofer not outputting as loud as before can have various reasons, from connection issues to receiver settings to subwoofer settings and placement.
Play bass-heavy music to ensure there’s nothing wrong with the track. Unplug and replug everything correctly to make sure of the connection, and then alter your speaker volume, equalization, and channel settings.
If they don’t work, move the woofer around the room and place some sound-absorption panels. Try a more powered amplifier, and lastly, tweak your AVR configs such as stereo mode, bass enhancer, sub volume, etc.