Probably one of the worst things a DJ can deal with is a malfunctioning subwoofer and in this article, we will take a look at how to tell if a subwoofer is blown, and also, can you fix a blown subwoofer.
This can be especially embarrassing if you are using your own kit and have to deal with a blowout while performing on stage or in front of an audience. Like at a wedding or private function.
A blown sub can be incredibly frustrating, as it means you’ve lost out on your wonderful bass almost instantly.
The good news is that not all hope is lost.
If you know what are the causes of a subwoofer blowout, as well as some of the common signs that you’re currently dealing with it, you can immediately get your sub looked at by a professional before causing more harm to the device.
In some cases, depending on the nature of the blowout, you may even be able to fix it.
In this brief guide, we’ll go over some of the causes of a blown sub as well as how to tell if you’re currently playing with one and don’t even realize it.
How To Tell If A Subwoofer Is Blown (in short)
There are several ways of telling if a subwoofer is blown, broken, or damaged. Subwoofers are more commonly blown by too much power being forced through them for a prolonged period of time. If you think you have a blown subwoofer check for a reduction in sound quality and listen for giveaway ‘crackles’. Perform an audio test, a full cone inspection, and use a multimeter to measure the amount of electrical voltage being put out through the sub’s coil.
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What Can Cause A Subwoofer Blowout?
If you’re dealing with a subwoofer blowout, take solace in knowing you aren’t the first and you won’t be the last.
Especially if you’re a performing mobile DJ, sub blows happen a lot more than people would like to acknowledge.
This is largely due to users using too much power for long periods or distorting the signal.
#1. Too Much Power
Probably the most common way subwoofers suffer a blowout is through an excessive cranking of power.
Pushing the sound and volume to its max for excessive periods, while it may be fun and exciting, continually strains both the speaker and the subwoofer.
After a prolonged amount of time, you’re going to push the sub past a point of no return and cause it to ultimately suffer some persistent damage.
While, yes, subs are generally able to handle more than their continuous power handling (also known as the RMS), that doesn’t mean you should crank it to its maximum settings for long periods.
If you do want to crank it up now and again, the sound should be as clear as possible and without any distortion.
A subwoofer that is dealing with high distortion, alongside a cranked-up volume, can be incredibly destructive to its internal structure.
Know the RMS wattage levels for your sub so that you always remain aware of how loud the sound should safely be to avoid any potential blowouts.
#2. Too Much Signal Distortion
While not quite as prevalent an issue as overpowering your sub speakers, signal distortion is another very serious problem for subwoofers and can cause them to suffer severe damage, if not an outright blowout, as a result.
Signal distortion generally happens when a user is trying to (ironically enough) improve the overall sound signal of the woofers themselves.
And while this may have some benefits in the short term, it can also be incredibly taxing. This is made even worse when you consider that a distorted signal can oftentimes be difficult to spot until after the damage has already been done.
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How To Tell If A Sub Is Blown
So you now know what are the main causes of a blown subwoofer.
That’s great!
The only problem is that, if you’ve been doing either of these things, there’s a chance your subs may already be blown and you don’t even know it.
Blown subs can be tricky to spot, in some instances, where the only sign may be the lack of bass where there used to be one.
However, if you know where to look for them, you’ll notice that all blown subs have at least a few of these issues present.
Here is how to know if your subwoofer is broken or blown:
#1. Altered Sound
Firstly, one of the big signs that you’ve dealt with a sub-blowout is by listening for a reduction in sound quality.
If you start hearing cracks and “crackles” in your audio, that may mean you’ve got a blown or damaged,
Performing An Audio Test
First, you’ll need to reduce the audio sound to a relatively low volume before commencing audio playback.
From there, slowly and methodically increase the sound’s volume and bass.
Throughout that time, you also want to keep your eye on the sound quality. Is it starting to come out distorted? Is the sound cutting out entirely?
If either situation is present, you know that the sub is suffering from either a partial or complete blowout and should be looked at immediately.
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#2. Damaged Speaker Cone
The next way that you can know if you’re dealing with a blown sub is by physically inspecting the speaker cone for any damage.
To do this, remove the speaker’s cover to access the speaker’s cone. From there, carefully look it over for any signs of damage.
You can use either hand to press along the sides of the cone to feel for any tears or breakages.
It’s important to keep in mind that you don’t exert too much force or pressure while inspecting the speaker cone.
If the cone moves more than it should (or doesn’t move at all), you know that the sub has a blowout.
On the other hand, even if it has the right amount of push, you want to be on the lookout for any scrapes or scratching sounds as these could be signs of early damage to the cone’s integrity, which will later turn into a blowout.
#3. Damaged Coil (Lack Of Electrical Resistance)
Lastly, by using a multimeter to measure the amount of electrical voltage, current, and resistance being put out, you can determine if there has been any damage to the sub’s coil.
One of the clearest signs that the sub has been blown is if the electrical reading is sporadic and all over the place.
Measuring A Subwoofer’s Resistance
To measure your sub’s electrical resistance, first, disconnect the device from its existing power source as well as any audio input it may be connected to.
If your sub isn’t using an external amp or receiver, you’re going to need to take it out of its enclosure.
Afterward, connect both probes to the multimeter to measure the device’s ohms.
You’ll want to make sure you’ve installed the red probe into the positive lead while the black probe is put into the negative lead.
This will allow the multimeter to measure how much resistance is available. You’ll want to round the number out to the nearest number (either up or down) to determine an accurate resistance number.
Can You Repair A Blown Subwoofer?
As it stands, there are only certain specific instances where a blown subwoofer can be repaired.
Generally, in most cases, you’re going to need to break down and just buy a new speaker and be more careful.
Either way, the best way to determine if the sub can be prepared is by disconnecting it from your speaker setup and taking it to be thoroughly inspected by a professional.
I always recommend taking it to at least two or three professionals, as that way I can both know if it actually can be fixed while also having some different prices to compare with one another.
If you’ve only had your speaker for a relatively short amount of time, consider seeing if the warranty has finished up. If it’s still valid, you may be able to get a new one completely for free (if not this one is properly repaired).
One important thing to note is that many warranties become void if you’ve tampered with or disassembled the sub before having it professionally looked at.
As such, always check the manufacturer’s warranty validity before doing anything to your sub. If the warranty is still valid, just take it to a professional.
Only consider checking for yourself if the warranty allows disassembling or has already expired.
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How To Tell If A Subwoofer Is Blown: Takeaway
Subwoofers are an important part of any DJ’s speaker setup.
They are instrumental in allowing those crowd-pleasing beat drops and work to make a sound that much more pleasing than otherwise.
Subs can be an expensive option if you aren’t aware of what to look out for.
By taking the time to know how to avoid a blowout, as well as whether you’ve already had one, you can effectively safeguard yourself from any issues as well as know if you need a new speaker right away before dealing with any additional damage.
