How to Fix a Blown Subwoofer

The subwoofer is the component of a stereo system that provides low bass frequencies. When the standard speakers bow out and are not able to provide the low-frequency sound waves, the subwoofer steps in. There are two types of subwoofers: passive and powered.

Powered car subwoofers are less common but are the preferred type. They require their own power supply from either the amplifier or stereo receiver to operate the internal amplifier. The passive subwoofers have no built-in amplifier and can access power only from an external amp.

How Do you Know When Your Subwoofer is Blown?

Before fixing the blown subwoofer, you need to determine first which subwoofer or speaker has blown.

Steps To Find Which Subwoofer Or Speaker Is Blown

Get rid of other noises. Keep the subwoofer on that you think is broken, and turn off all other speakers. If you are not certain which subwoofer or speaker is broken, it is best to test them one by one. Get rid of noise around the car as much as possible. If you are in a car, turn the car off and park it in a quiet place. Through this, you can isolate the issue with the subwoofer.

Is the Subwoofer Fully or Partially Blown?

After isolating your subwoofer, play any type of sound. Place your ear near the subwoofer. If there is another sound or if you can hear hiss, then it has probably fully blown. Increase the volume as you listen to the subwoofer. If the subwoofer seems to produce normal sound at low volume, but it is bad when you increase the volume, then it could be partially blown. The most obvious sign of a broken subwoofer is if it does not emit any sound.

When Subwoofer Is Not The Problem

If you hear a rattling sound in the car sound system, this has nothing to do with the subwoofer. It could be caused by a loose screw or other object placed against the subwoofer.

When in use, subwoofers vibrate visibly. Observe the front of the subwoofer as you play a heavy beat song. If it is working properly, you will see that the subwoofer is vibrating. By touching the front of the subwoofer, you can feel if it is vibrating or not. You can also feel the vibration of the subwoofer if you increase the volume and bass. A blown subwoofer does not vibrate at all.

Using A Multimeter To Check If A Speaker Is Broken

Multimeters are helpful tools that measure voltage in your car. Most expert audio repair technicians use a multimeter to check if speakers are broken. Turn off the subwoofer and set the multimeter to read ohms. If you have an AMM multimeter, it should be at zero before using it. Place it on the subwoofer’s terminals and observe the reading. If it is positive, the speaker is working. If it remains at zero, there is a problem. If you get an infinity reading, the voice coil is damaged.

Fixing the Blown Subwoofer

What you need:

-Screwdriver Reconing Kit (cone, spider, voice coil, surround and glue)

-Compressed air

-Putty knife

-Soldering Iron

Steps to Fix a Blown Subwoofer

Step 2

Remove the surround from the speaker edges using the putty knife. Ensure that all the surround and glue are removed from the frame.

Step 3

Pry out the voice coil and speaker cone using the putty knife. Use the knife to cut the terminal wires from the voice coil, and then take the old cone, spider and coil out.

Step 4

Remove the dust particles from the voice coil gap using the compressed air. Place the new voice coil in the gap. Put the spider around the voice coil. Put enough glue to the cone, then fit and place the cone in the center of the voice coil. Allow it to dry for 24 hours.

Step 5

Put enough glue on the surround and place it slowly on the edges of the speaker frame and cone. Allow it to dry out for 24 hours.