How To Test A Subwoofer With a Multimeter? 5 Simple Steps

Nowadays, blown-out subwoofers are a typical issue, and you might not even be aware of the damage. Having a blown-out subwoofer generally results in hearing severely distorted sounds, ruining your entire experience regardless of how old or costly your subwoofer is. A subwoofer issue might have a negative impact on the audio quality. Testing your subwoofer with a multimeter is the best option in this situation.

This post will show you how to test a subwoofer with a multimeter in a few simple steps.You may detect the following important factors by testing your subwoofer:

• How serious is the breakage? The sub can be broken or simply be in the wrong place, producing a low-quality sound.
• What’s the cause of this? There are some parts that might wear out or get blown out.
• What to do: Once you have a complete picture, you may determine whether to repair or replace the subwoofer.

How Does a Subwoofer Work?

Any sound system must have a subwoofer since it is a loudspeaker designed primarily to create low-frequency sound. The majority of subwoofers are powered, but some are passive and require an amplifier connection to be functional.

The music system’s woofers receive the sound waves from the subwoofers, which produce the bass frequencies that are audible. Subwoofers with built-in amplifiers are not universal. Some of them may require the use of an external amplifier.

How do we know that our subwoofer is not working properly?

A subwoofer surely has the most impact on the sound quality of your system. So, if something is wrong with your subwoofer, you’ll be able to notice it easily. The sound output is pretty straightforward, and you can see the effect right in front of you. If the sound is distorted or breaks out between frequencies, the subwoofer will burn out.

Aside from that, the subwoofer may have burned out if you observe any deterioration in it. However, only observing the noise cannot indicate if it has been blown away or if there are any additional issues. In order to determine whether the subwoofer is dead, you should test it.

How to Test a Subwoofer with a Multimeter

Connect the multimeter probes to the positive and negative terminals of the subwoofer’s voice coil after setting it to the ohms setting, specifically in the 200 Ohms range. It is good if you get a reading between 1 and 4, If it shows no resistance, the subwoofer is probably blown.

We will go through each and every vital step in detail.

Step 1: Unplug the Subwoofer from its power source.

Firstly, obtain your tools and unplug the subwoofer from the power supply. Depending on whether the subwoofer is active or passive, this operation may be as simple as disconnecting it from its external amplifier or disconnecting it from your car battery.

Step 2: Remove the Subwoofer from its enclosure.

Once the subwoofer has been unplugged from the power supply, you can take it out of the vehicle without any risk. However, depending on the design of the subwoofer, you may need to remove the cone from the enclosure to access the wire coil.

Step 3: Insert the multimeter probes into the voice coil terminal

After removing it from its enclosure, insert the multimeter probes into the subwoofer cone’s wire coil input terminal. These are red and black, matching the multimeter’s red and black probes. Connect the multimeter probes to the similarly coloured terminal on the subwoofer speaker. Before turning on the multimeter, be sure they are completely inserted.

Step 4: Set the resistance of the multimeter in Ohms.

 To check for faults, you must measure the resistance of the subwoofer. To measure resistance, place the multimeter’s dial in the Ohms range. Turn on the power and set the front dial of the multimeter to ohms. A reading should appear immediately on the digital display panel.

The Omega Symbol symbolizes the Ohms setting on the multimeter (), which has many ranges (2M, 200, 2k, 20k, and 200k).

You should set the multimeter to the 200 Ohm limit since it delivers the most exact readings. Compare the positive and negative leads to verify if the multimeter is properly configured.

The multimeter will beep if all is set up correctly when in continuity mode, or it will display a value close to zero when the Ohms setting is applied. If you obtain them, then go to the next level.

Step 5: Evaluate the Results

The multimeter should give you a reading between 1 and 4 depending on your subwoofer. If it displays no resistance, the subwoofer is most likely blown, and if it produces a lower value, it should be removed. Furthermore, if the task drifts too frequently, the voice coil may be blown.

Ways of testing Subwoofer without an Amplifier

The voice your subwoofer produces is a simple way to test it. Having an amp for that is relatively helpful in figuring out what’s wrong with your subwoofer.

There is a method if you want to test your subwoofer without using the amp. You’ll need a 9-volt battery, a tester or multimeter, and a wire to do so. Connect the subwoofer and battery by taking the wire and connecting the positive terminal of the coil to the positive terminal of the 9-volt battery. It would be preferable if you did the same on both ends.

Once the battery has been connected correctly, evaluate whether the woofer’s cone is rising. If your subwoofer works properly, it should begin to rise as soon as you connect the battery. And it should go down when you disconnect.

In such cases, use a tester or multimeter to determine if the subwoofer has blown out. In order to determine the subwoofer’s resistance, use the method from before to do it. If the value is less than 1 ohm or more, your woofer will blow out.

This is a great way to find out if your subwoofer has to be fixed because it is blown out or if there are other issues.

CONCLUSION

In conclusion, testing a subwoofer with a multimeter is a straightforward process that can help you diagnose common issues and ensure your audio system is performing at its best. By following the five simple steps outlined in this blog, you can verify the impedance, check for continuity, and confirm the functionality of your subwoofer’s voice coil and connections.

Whether you’re troubleshooting a subwoofer that’s producing distorted sound or simply performing routine maintenance, using a multimeter is a valuable tool for any audio enthusiast or technician. Remember to exercise caution, use the correct settings on your multimeter, and consult the subwoofer’s specifications for impedance values. With these skills, you can enjoy high-quality, booming bass in your audio system while keeping your subwoofer in excellent working condition.

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