How To Tell If Subwoofer Is Blown? 5 Ways To Know

While a speaker produces low bass frequency ranges, a subwoofer plays a vital role in delivering fresh, full output when you listen to music. If you notice that the bass is not as smooth as usual or disappears, there’s a high chance something has gone wrong. But how to tell if subwoofer is blown?

There are a few easy tests you can run to confirm this. Our article will thoroughly guide you to perform each test and give you some helpful tips.

What Do Blown Subwoofers Sound Like?

A blown sub sounds awful and distinctive since the cone moves inside and outside without bass from the loudspeaker.

This problem often produces a ‘hissing’ or ‘whump,’ yet not all damaged subs produce that noise.

A blown driver can make different sounds, but the most usually seen signs of blown subs are:

  • Delivering bass that sounds weak and thin, barely noticeable, or even no bass
  • Loud distorted bass
  • A rattling sound from inside

Why Do My Subwoofers Blow?

How To Tell If Subwoofer Is Blown? - Too much power could damage your subs.

Too much power could damage your subs.

A subwoofer gets blown when it receives too much-distorted signal or excessive power.

Excessive Power

The most common reason for many subwoofers getting blown is excessive power.

Listening to music at high volumes is many people’s hobby and seems exciting, but please remember that a subwoofer can’t always handle much work.

If you push it to work beyond its capacity, it’ll have to face excessive pressure, which is the ultimate cause of damage.

That’s why it is paramount to know your device’s RMS wattage as you can ensure you’re providing it with the right degree of power.

Distorted Signal

On the other hand, if the device is short of adequate power, it will overheat and create distorted signals. These signals may induce the sub to malfunction while the amplifier has power.

Many people raise the volume to promote sound quality when hearing distorted signals. However, this act only helps produce crackling sounds or sustained clipping when the volume increases.

Indeed, it’s pretty hard to detect distorted signals early, complicating the issue.

Broken and Rusted Parts

Sometimes, electrical problems like loose cable connections can be the reason.

Though it’s rare, it may happen if you don’t connect the wires securely or insulation doesn’t cover the cable joints.

Condensation in bad connectivity poses high resistance, leading to overheating. Also, if there’s rust on metal parts, there’s a high chance they will break under heavy pressure quickly.

A rusted seam or terminal will make it hard for the voice coil to contact the pole component. It generates overheating and resistance, resulting in a blown sub and shortened component.

Mechanical Failures

Besides electrical accidents, mechanical ones can also damage the speaker’s components that support or protect it, eventually causing a blown sub.

The most recommended way to prevent mechanical issues is through appropriate maintenance and care for your equipment.

So, inspect your subs and speakers for symptoms of wear or damage regularly and remove them before the damaged parts wreck your stereo system.

How To Tell If Subwoofer Is Blown?

Below are five techniques to analyze and detect the damage, if there is any. From there, you can determine whether the subs have gone broken or not.

Test The Sound

How To Tell If Subwoofer Is Blown? - The sound from a broken sub won’t be fresh and clean.

The sound from a broken sub won’t be fresh and clean.

The output you are hearing is an apparent indicator showing the damage level. You can get three results, depending on how damaged the subwoofer is:

  • No sound: A clear sign that the equipment has entirely blown.

Still, before reaching this conclusion, you should test the cables and audio resources properly and ascertain you’ve powered the amp.

If your sub refuses to work even when your amplifier has power, watch this video for some tips to fix the situation:

If it still fails to work correctly, it is safe to conclude the equipment has gone broken.

  • Partial output with distortion: Distorted, weak sounds can mean your equipment has partially blown.
  • Scratching sounds: These sounds usually imply something wrong with the cone. In this case, you’d better replace it.

Test The Cone

Another easy approach to identify problems is to access the sub cone. Proper operation of sub cones is thanks to the suspension system, allowing them to move fluidly.

You can effortlessly determine if the cones are off with your hands. Press the sub cones lightly and carefully, and you may experience:

  • Scratching noises: The damage has happened if the cones make scratchy sounds while you stir them using your hand.

You need to remove them from your theater system immediately before they damage other pieces of equipment.

  • Wobbly cones: Their suspension systems pose harmful effects if the cones stir around unsteadily.
  • No movement: If you notice no movement from the cones, there’s high chance damage has happened.

Test The Resistance

How To Tell If Subwoofer Is Blown? - A multimeter will help you check if the coil is damaged easily.

A multimeter will help you check if the coil is damaged easily.

A must-have tool that helps simplify the work is a multimeter when it comes to testing the resistance.

It will tell you whether your subwoofer has a damaged coil or not and show you the electrical resistance.

If there’s zero resistance or the reading doesn’t stand in place, the coil suffers damage.

In particular, follow the below instructions to measure a subwoofer’s ohms or electrical resistance:

  • Disconnect the sub from the power source
  • Detach the sound input from your subwoofer
  • You’ll need to detach your sub from the enclosure unless you power it using an external receiver or amplifier.
  • Attach the probes to your multimeter, then turn it on to measure the resistance (Ω).
  • Insert the black probe into the (-) lead while the red one goes into the (+) lead.
  • After that, the multimeter will read the degree of resistance.

Voltage Check

We usually measure the bass produced by a sub in watts. Yet, you should go through the voltage to determine if one has broken or not.

First, install a voltmeter. Then, attach the tool’s (+) lead to a cable running from the amp’s speaker terminal.

Use a small alligator clip to touch the two sides where you connect your loudspeaker terminals.

In so doing, you can measure the amount of voltage going through the amplifier without manually touching any connection.

If the voltmeter shows no reading, there’s a high possibility that your sub has broken or there is some work to do with it.

Physical Inspection

How To Tell If Subwoofer Is Blown? - You can inspect the sub’s physical conditions manually.

You can inspect the sub’s physical conditions manually.

Sometimes, simply pressing on your subwoofer can tell whether it’s broken. An efficiently working subwoofer will have suspension that enables movement.

Gently press on two sides of your sub’s speaker cone using two hands. If you notice rigidness or no movement, you can say for sure damage has happened.

Even when the cone stirs, listen carefully to identify any scratching noise.

Be mindful of any movement that is too sluggish or loose. These are all potential signs of worn suspension.

What To Do With A Blown Subwoofer?

While you can fix a blown subwoofer in some circumstances, it’s better to purchase a new model in most cases.

The first step is always to disconnect the equipment from the theater system since it could pose more harm to other devices. You don’t want the matter to become more stressful and complicated, right?

Next, ask a professional to help inspect your equipment who can predict the potential deterioration of the matter.

If you detect the problem not long since you bought the product, check if it’s still within the warranty time.

If yes, lucky you! You can bring it to the manufacturer for help. So, remember to check the warranty’s validity before disassembling the device.


Like any other audio-related topic, there will be extra concerns that home theater owners may have, for example:

  1. Will A Blown Sub Still Make Noise?

    While a broken sub may stream crackling, distorted sounds, it will refuse to work correctly in the designed capacity.

    In most circumstances, a damaged device will stop functioning entirely. You can choose to buy another product or repair the broken one.

  2. Is It Worth Repairing A Subwoofer?

    Though you may attempt to repair the worn equipment because of the sentimental accessories, the repair is often not as cost-effective as a replacement. In other words, it’s not worth repairing.

    Besides, the repair requires specialized knowledge and specific components that might cost more than buying a new product.

  3. Why Did My Subs Stop Working All Of A Sudden?

    The most commonly encountered cause of sub malfunction is short-circuiting. A short circuit prevents the signals and electrical current from reaching the sub.

The Bottom Line

If you are experiencing an audio problem with your subwoofers, the first step is to check whether it has blown.

The above tactics have instructed you how to tell if a subwoofer is blown quickly, whether it’s a frequent or occasional occurrence.

We hope you know what to do with your equipment now.

See you in the next article!

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