How to Fix Blown Subwoofers

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Updated December 2, 2022

Learning how to repair blown subwoofers is important to ensure audio quality over time, especially if you have top-tier speakers. Exceeding the recommended bass levels on your system can cause internal damage, even on premium subwoofers. So, if you hear that terrible scratching sound from your faulty subwoofer, you can fix it at home. While repairing a damaged speaker cone sounds complicated, it is simple with this step-by-step guide. Stick around to learn how to fix blown subwoofers and restore your quality sound.

KEY TAKEAWAYS:

  • Remove your subwoofer from the speaker frame, and test your voice coil with a multimeter.
  • Uninstall the speaker cone, voice coil, and spider, then disconnect your speaker wires.
  • Install the voice coil, glue the cone, top plate, and foam surround into place, and let it dry before reconstructing your speaker frame.

Blown Subwoofer Repair

Your subwoofer can take damage from situations like amplifier clipping, excessive sound, or power signals. So, if you’ve learned how to get deep bass from a subwoofer, do not overwhelm it with too much power.

Insider Tip

After deconstructing your defective subwoofer, use tape to remove dust particles from the voice coil gap.

Also, if you hear a distorted sound or have no audio signal at all, you should learn how to fix a subwoofer with no sound. Unseen damage usually indicates a bad voice coil, but torn subwoofer cones are easily detectable.

Once you’ve completed the restoration process on your broken subwoofer, consider learning how to hide a subwoofer. Humans cannot easily detect the source of low-frequency sounds, so your subwoofer placement isn’t a massive variable for sound quality.

STEP 1 Remove the Subwoofer from the Enclosure

With a screwdriver, remove the screws holding the subwoofer in the enclosure and pull it out.

STEP 2 Test the Voice Coil for Damage

Connect a multimeter to your speaker terminal wires and check for electrical resistance. If you see resistance, your voice coil is fine, and you can simply perform a cone replacement. That said, you may want to replace the voice coil anyway, especially if you’re working with older subwoofers.

STEP 3 Remove the Top Plate and Speaker Surround

Use a heat gun for a few minutes to loosen the glue on the top plate and outside edge. Then, use a sharp blade or flathead screwdriver to pry the top plate and foam surround away. Do not damage this plate, and clean the old glue from the center and edge.

STEP 4 Remove the Cone and Voice Coil

Use a screwdriver and sharp blade to remove the speaker cone, voice coil, and spider. Disconnect the voice coil wires if you haven’t already.

STEP 5 Clean Your Components

Ensure your hardware is clean before reassembling the speaker unit. You can use an air compressor or microfiber cloth to remove dust or debris from the subwoofer.

STEP 6 Install the New Parts

Slide your voice coil into the voice coil gap in the spider, and glue the cone plate on the center and sides of the frame. Ensure the cone and voice coil are centered in the spider and allow the glue to dry for at least 24 hours.

STEP 7 Reconnect the Subwoofer

Reconnect the speaker wiring and reinstall the subwoofer into the speaker frame. Test your work.

Warning

Never run your car audio system at full volume on a cold morning because a frozen subwoofer needs to warm up to avoid speaker cone tears.

STAT: A 2019 Noise Health survey found that women preferred an average 71-decibel listening volume regardless of their headphone type. (source)

How to Fix Blown Subwoofers FAQs

Do I need an external amplifier for my subwoofers?

Audio amplifiers boost the input signals of your sound system, but powered subwoofers and speakers often feature a built-in amplifier. That said, your subwoofer should have plenty of power for bassier sounds and low frequencies. So, many users opt for an external amplifier box to bolster those frequencies.

What can blow subwoofers?

The most common cause of blown subs is setting the volume above the recommended sound levels for your system. That said, your power source can also cause a subwoofer tear or coil damage. Over- or underpowering your subs can cause extreme damage to the unit.

What do blown speakers sound like?

A blown subwoofer or speaker will produce a distorted signal, scratchy sounds, or an annoying buzz. If your equipment has suffered severe damage, bad sounds will even occur when you're not playing music.
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