A subwoofer is a durable piece of equipment. When the subwoofer smells like it is burnt, it’s best to troubleshoot things immediately. But the reason for the burnt smell should not be difficult to find.
The problem always comes from the power that the speaker produces. When the frequency is either too high or low, it causes the voice coils to burn. As a result, your subwoofer will smell burnt when you switch it on.
When your subwoofer smells like it is burning, it does not mean that your subwoofer is already useless. The reason is that you can still have it fixed.
What is even better is that there are things that you can do to prevent your subwoofer’s voice coils from burning. After all, if your subwoofer smells like burning, it’s only a matter of time before a fire starts.
Also read: What to do when an AVR Power Supply Smells Like Burning Plastic
Causes for Your Subwoofer Smelling Burnt
If you are looking for a sound system that can reproduce low frequencies, then a subwoofer is what you need.
Subwoofers can smell like they are burning for a number of reasons including faulty wiring, dust build-up, improper input signals, and aging components.
Regardless of how loud or soft the music you are playing is, a high-quality subwoofer can improve your overall listening experience.
There is no doubt about the durability of a good subwoofer. However, there are times when they suddenly smell like burning. Such is an indication that an issue within the speaker awaits fixing.
Moreover, there are two reasons why your subwoofer smells like it is burning all of a sudden:
- Over-powering low-frequency speakers
- Over-powering high-frequency speakers
Over-Powering Low-Frequency Speakers
A burnt smell in a subwoofer is commonly due to either electrical or mechanical failures.
Electrical failures in a subwoofer happen when you apply too much power to the equipment.
Subwoofer assemblies will have a specific range and rating. Typically there is a placard on the rear of the device that states the specifications.
In cheap models of subwoofer, there may not be any identification to tell you the specific devices specifications. In this case, it is best to use caution when applying power to the device.
When there is too much power, the voice coil burns, such damage can occur when the subwoofer wiring is faulty or the gain is incorrectly set. This issue results in impedance load on the equipment’s amplifier.
On the other hand, a mechanical failure on the subwoofer occurs when the speaker wears or tears physically. When the size of the sub’s enclosure is incorrect, mechanical failure happens.
A rule of thumb is that a subwoofer enclosure should always stay within more or less 25 percent of the recommended enclosure volume from the manufacturer. Such will ensure the speaker’s optimal performance.
If the enclosure of your subwoofer is too large, it will compromise the mechanical suspension of the equipment.
Moreover, using a subwoofer enclosure smaller than the manufacturer’s recommendation will not cause any severe effects in terms of power handling. It is even safer than using a larger one.
Another cause of a subwoofer’s mechanical damage is when the enclosure does not have enough ventilation. Tuning the equipment the wrong way can also compromise its mechanical handling power.
To ensure that your subwoofer’s enclosure matches the manufacturer’s recommendation, you should check the port length and diameter as well as the internal volume.
Over-Powering High-Frequency Speakers
Sometimes, you will notice electrical or mechanical damage to your subwoofer’s mid-range and mid-bass speakers or the tweeters.
If that happens, you should check if the high-frequency speakers are overpowering and burning the voice coil.
At first, too much power will not damage the voice coil. However, constant overpowering will cause it to burn. So, your subwoofer smells like it is burning when overpowered.
The only thing you can do to fix this issue is to reduce the gain controls of the amplifier along with the treble and bass boost controls.
In addition, you can readjust the settings of the subwoofer’s equalizer so you can maximize the equipment’s sound quality.
Moreover, mechanical failures brought about by over-powering high-frequency speakers happen when you are using an incorrect crossover point for your speaker.
Most of the time, when you apply a frequency that is too low to a small suspension driver, it damages the speaker and causes it to delaminate.
You can only prevent such a type of failure by following the guidelines for crossover slope and frequency given by your subwoofer’s manufacturer.
Repairing a Burnt Voice Coil in a Subwoofer
One important thing to note when repairing a burnt subwoofer voice coil is that it takes much work.
The main reason is that it connects to the other components of the equipment, which requires you to fix those components.
The first thing you need to do when fixing a subwoofer voice coil is to cut the braids and the spider. You are going to replace these components after repairing your sound system.
Since the voice coil connects to some other components, you need to remove the assembly framework.
Remember that you must take off the entire assembly in one piece. But if you cannot take off the components in one, you can use a heating gun to dissolve the glue that connects them to the enclosure.
Alternatively, you can use a sharp knife or blade when taking the components off.
Once complete, clean up the area where you removed the components. Scrape off the old glue and suck up the solder where the braids connect before.
Now, it is time to take the burnt voice coil off. To do this part, you can either cut or peel the coil.
After the voice coil removal, straighten out the cone neck that once held the old voice coil. It would help if you also cut or dissolve the old dust cap to remove it.
After cleaning the old voice coil area, use the new layout to measure the new dimensions. Doing such will help you when you are installing the new voice coil.
Once you are sure with the measurements, re-attach your new voice coil using glue.
Another thing worth noting is that your replacement should be precisely the same as the old one when replacing the voice coil.
If the replacement that you have is not the same, it will not vibrate right. As a result, your subwoofer will not produce good audio.
How to Take Good Care of Your Subwoofer
There is no denying that a subwoofer is a fantastic source of entertainment. Such is especially true if you are an audiophile. In addition, this type of speaker is also expensive, so you need to take good care of it.
A subwoofer is a costly investment. For this reason, you need to learn about a few maintenance methods that you can use to keep its structural integrity.
1. Place it in an area where it is safe from dust.
Your subwoofer mustn’t have dust buildup inside it. The reason is that dust can negatively affect the performance of the speaker. For this reason, clean your subwoofer from time to time by blowing away the dust using compressed air.
2. Avoid using liquid cleaners.
No matter how careful you are, there are chances that the liquid cleaner you are using will infiltrate the internal area of your subwoofer. If such happens, you will compromise and damage the amplifier. For this reason, go for using a dry method when cleaning your subwoofers.
3. Check if you did the plugging correctly.
Wiring is an integral part of a subwoofer. For this reason, you should check if all the plugs are placed and connected correctly. If you plugged a jack into an incorrect channel, chances are it will blow up your sound system.
4. Provide enough ventilation
Heat is an element that can damage your subwoofer. For this reason, place the equipment somewhere where it gets proper ventilation. This way, you will be able to prolong the life of your sound system.
Sources
- How do speakers get blown? Why do they sound distorted? RF Tech, http://rftech.custhelp.com/app/answers/detail/a_id/63/~/how-do-speakers-get-blown%3F-why-do-they-sound-distorted%3F/
- How to Repair & Fix Speaker Coil Faults, Electronic Notes, https://www.electronics-notes.com/articles/audio-video/loudspeaker/repair-replace-speaker-coil.php/
- Victor Epand, The Best Ways To Maintain Your Speakers, Street Directory, https://www.streetdirectory.com/travel_guide/115205/electronics/the_best_ways_to_maintain__your_speakers.html/
Jason is a home theater expert with over 10 years of experience in setting up home cinema rooms and systems. What started out as a hobby soon transformed him into an authority in the audio-visual field. He is passionate about providing readers with accurate and up-to-date information on the latest audiovisual technologies and their applications for home theaters. Read more about Jason.