Skip to Content

Bass Drop Blues: How to Fix a Blown Subwoofer

If you’re an audiophile, you know how important subwoofers are for a great audio experience. And when it comes to home theaters, that bass is the difference between an exciting action scene that gets your heart racing or not. But even the best subwoofers can blow out if not taken care of properly. That doesn’t necessarily mean you have to buy a replacement though.

If your subwoofer won’t make sound, or is producing distorted or buzzing sound, the subwoofer could be blown. Look for tears in the cone or spider, and/or check it with a multimeter diagnose a blown voice coil. You can repair a subwoofer yourself pretty easily.

So, if you’re facing a blown subwoofer, don’t worry – we’ve got you covered. In the following sections, we’ll cover everything you need to know to fix a blown subwoofer. From assessing the damage to replacing the damaged parts, we’ll step through the things you need to do to repair your subwoofer before discussing how to prevent this happening to you again in the future!

Identifying a Blown Subwoofer

The first step is going to be to identify whether or not your subwoofer is actually blown. So what signs should you be looking for?

Signs of a Blown Subwoofer

  • No sound: If your subwoofer is not producing any sound at all, it is likely that it is blown (though, of course, you should confirm this isn’t a volume or wiring issue first).
  • Distorted sound: If the sound coming from your subwoofer is distorted, it could also be a sign that it is blown.
  • Buzzing: If you hear a buzzing sound coming from your subwoofer, it could be a sign that the voice coil is damaged.

Have a look at our full article on spotting a blown subwoofer if you’re still not sure.

Checking A Subwoofer With A Multimeter


Using a multimeter is a quick and easy way to test if your subwoofer is blown, but you probably don’t have one laying around. If you do have access to a multimeter like this one (on Amazon), you can use the steps below to check your Subwoofer.

If you don’t, don’t worry about it – we’ll be taking the thing apart to try and visually confirm what the problem is in the next step!

  1. Set your multimeter to measure ohms (Ω).
  2. Disconnect the subwoofer from the amplifier and make sure it is not touching anything else, which would interfere with the readings.
  3. Connect the multimeter leads to the subwoofer terminals (the place where wires connect to it on the back)
  4. If the multimeter shows a reading of 0 ohms or infinite ohms, this is a pretty good indication that your sub is blown. It should be reading some value of resistance, so, 0 means there’s no connection and a physical failure somewhere, likely in the voice coil itself.

And remember, earlier we recommended you also confirm the actual, literal cables are still working. Sometimes that’s all that the problem is: old cables.

Assessing the Damage

To fix anything, obviously we’re going to need to get in there and figure out what’s busted. In this section, we will go through the three main parts of a subwoofer that you need to examine: the voice coil, speaker cone, and suspension system.

And grab your screwdriver–this is the part where we’re going to start disassembling things so we can get this better look at them.

Pro Tip: as you begin to disassemble the speaker, work in a space with plenty of room where you can stay organized, to help you reassemble the speaker when you’re through.

Examining the Voice Coil

The voice coil is the thin wire that is wrapped around a cylinder inside the subwoofer. It is responsible for producing sound by moving the speaker cone back and forth. To assess the voice coil, you need to check for any damage or signs of wear. A damaged voice coil can cause the subwoofer to produce distorted or no sound at all.

One way to check the voice coil is to use a multimeter. Follow the steps in the previous section to use the multimeter. If the reading is zero or infinite, the voice coil is damaged and needs to be replaced. You can find a replacement voice coil on Amazon.

Checking the Speaker Cone

The speaker cone is the main component that produces sound in a subwoofer. It is a thin, flexible material that moves back and forth to create sound waves. To check the speaker cone, you need to look for any signs of damage or wear. A damaged speaker cone can cause the subwoofer to produce distorted or no sound at all.

One way to check the speaker cone is to gently press down on it with your fingers. If it moves freely and smoothly, it is most likely in good condition. If it feels stiff or there are any tears or holes in the cone, it needs to be replaced.

Inspecting the Suspension System

The suspension system, also known as the “spider”, is the component that holds the voice coil and speaker cone in place. It is a thin, flexible material that allows the speaker cone to move back and forth while keeping it centered. To inspect the suspension system, you need to look for any signs of wear or damage.

One way to check the suspension system is to gently push down on the speaker cone and watch how it moves. If it moves smoothly and returns to its original position, the suspension system is most likely in good condition. If it feels stiff or there are any tears or holes in the spider, it needs to be replaced.

Ask Yourself: Is It Worth It To DIY Fix Your Subwoofer?

If the damage is minor, such as a simple tear in the cone or a loose wire, then it may be worth it to try and fix it yourself. However, if the damage is more extensive, such as a failed voice coil, then it may be more cost-effective to replace the unit.

If you have experience working with audio equipment and feel confident in your ability to fix the subwoofer, then it may be worth it to try. However, if you’re not familiar with the inner workings of subwoofers and don’t have the necessary skills, then attempting to fix it yourself may do more harm than good, and it may just be frustrating.

We’ve been around the block when it comes to home theater DIY projects, and failed speakers, 9 times out of 10, just need to be replaced in our experience. Especially if they’ve been blown through aggressive use, indicating that you probably need a replacement that’s larger and more powerful.

Depending on the extent of the damage, you may need to purchase replacement parts, such as a new cone or voice coil. If the cost of the materials needed to fix the subwoofer is significantly less than the cost of a new unit, then obviously you’d probably be better off just getting a new one.

If you do decide to DIY fix your subwoofer, make sure to purchase high-quality replacement parts. Note that you can get cone repair kits like this one (on Amazon), and other speaker repair kits, but they typically need to be sized to the speaker you’re working on.

Prepping Materials for Your Subwoofer Repair

Before we start repairing the subwoofer, we need to make sure we have all the necessary tools and materials. Here are some of the things you’ll need:

  • Screwdriver set: You’ll need a screwdriver set with multiple sizes and types of screwdrivers to remove the subwoofer from the enclosure and disassemble it.
  • Air compressor: An air compressor can be used to remove dust and debris from the subwoofer’s components and enclosure. It can also be used to clean the soldering iron tip. Simple canned air will do.
  • Putty knife: A putty knife can be used to remove the adhesive and glue from the subwoofer’s components and enclosure.
  • Adhesive and glue: You’ll need adhesive and glue to reattach the components to the subwoofer and enclosure after the repair is complete. A hot glue gun (on Amazon) is great for this.
  • Microfiber cloth: A microfiber cloth can be used to clean the subwoofer’s components and enclosure without leaving any scratches.

And here ere are some of the more exotic/advanced tools we recommend having on hand if you can, but don’t go out and buy them just for this:

  • Heat gun: A heat gun can be used to soften the adhesive and glue on the subwoofer’s components and enclosure, making it easier to remove them.
  • Multimeter: A multimeter can be used to test the subwoofer’s components and wires for continuity and resistance.
  • Desoldering pump: A desoldering pump can be used to remove excess solder from the subwoofer’s components and wires.
  • (Maybe) A Soldering iron: A soldering iron is required for repairing damaged wires and components on the subwoofer. Make sure to use a soldering iron with adjustable temperature settings to avoid damaging the subwoofer.

Having all the necessary tools and materials will make the repair process smoother and more efficient. And what you need will be based on the damage you found in the inspection. But get your materials ready, with the speaker, and get them all set out in a space for you to work.

5 Steps To Fix Your Blown Subwoofer

Anatomy of a Sub
Courtesy Accuracy Pro Audio

So, this can be daunting, but, really, there are only 5 steps to repairing your subwoofer:

Step 1: Unscrewing and Removing the Subwoofer

This is where our adventure begins. Start by turning off your sound system and unplugging your subwoofer to prevent any electrical accidents.

Use a screwdriver to carefully unscrew the subwoofer from its enclosure. Depending on your subwoofer model, the number and location of the screws may vary, so be sure to check the user manual if needed.

As you remove the screws, keep them in a small bowl or container so they don’t get lost. Gently pull out the subwoofer, being careful not to yank any connected wires.

Step 2: Replacing the Voice Coil (if Needed)

The voice coil is essentially the heart of your subwoofer, and it’s what vibrates the cone to produce sound. To inspect the voice coil, you’ll need to remove the speaker surround – that’s the outer edge that connects the cone to the frame.

Look for any signs of damage such as burns, deformation, or unwinding. If you spot any of these, it means your voice coil is indeed blown and will need replacing. Be sure to order a replacement that matches your subwoofer’s specifications.

Step 3: Replacing the Cone (if Needed)

The cone, being the most visible part of your subwoofer, is quite straightforward to inspect. Look for any tears, holes, or other visible damage. If you notice any, it means your cone needs to be replaced.

As with the voice coil, ensure that your replacement cone matches the original in terms of size and material.

Step 4: Re-assembling everything

Once you’ve got your replacement parts, it’s time to put everything back together. Following the reverse order of what you did during disassembly, carefully install the new voice coil or cone back into the speaker box, along with the rest of the assembled parts.

Ensure that the voice coil is properly centered to prevent it from rubbing against the magnet. Once everything is in place, reattach the speaker surround and secure the cone.

Step 5: Testing and Reinstalling

Before you put everything back into the enclosure and screw it shut, it’s a good idea to give your subwoofer a quick test. Connect it to your amplifier and play some music at a low volume.

If everything sounds good, go ahead and reinstall your subwoofer into its enclosure. Replace the screws you had removed earlier, ensuring that the subwoofer is securely fastened. And just like that, you’ve successfully repaired your blown subwoofer!

How To Prevent Blowing A Subwoofer?

Dual Subs Rear

One of the main causes of a blown subwoofer is overpowering. To prevent this, we need to ensure that our subwoofers are getting the correct amount of power. We can do this by matching the power rating of our subwoofers with the power output of our amplifiers.

We can also adjust the amplifier’s power output to ensure that it’s not too high for our subwoofers. It’s important to note that if our subwoofers are underpowered, they can also get damaged. Therefore, we need to ensure that our subwoofers are getting enough power to function optimally.

Another factor that can cause a blown subwoofer is playing music at high volumes for extended periods. This can cause the subwoofer to overheat and get damaged. To prevent this, we need to be mindful of the volume levels we use when playing music. We can also invest in subwoofers with built-in cooling systems or use external cooling systems to prevent overheating.

These are the main ways you can blow a subwoofer, though there are a few other reasons this can happen ultimately. If you practice good listening habits – keeping volume reasonable most of the time and matching equipment based on specs – you can avoid blowouts for the entire life of a subwoofer.

Bringing Back The Bass

Maybe by now you’ve gained valuable insights and practical steps to bring your subwoofer back from the dead. From understanding what a subwoofer is, through to identifying the tell-tale signs of a blown one, and finally, the step-by-step process of repairing it, you’ve come a long way in this article and you should pat yourself on the back.

When it comes to home theater audio, the speakers make all the difference, and the subwoofer especially can make a huge impact. So, be sure to treat yours well to avoid blowouts in the future, but maybe now you’ll be ready to fix it yourself!