Car Speakers – Why They Blow

Car Audio Troubleshooting

Car speakers could sound great one moment and terrible in just a few moments. But what causes them to blow? In this article, we'll walk through the steps to identify if your speakers are blown, what may have caused them to blow and what to do about it.

Are My Car Speakers Blown?

People use the term “Blown” loosely when they're talking about speakers. In almost all cases, they just mean that the speaker is broken or something critical to the speaker has failed. Blown could be a speaker that doesn't work at all, or it could be a speaker that sounds like it's crackling, muffled, or just terrible in general.

If your speakers are blown, it's pretty simple to tell. Just listen. If you're experiencing any of the following with your speakers, they're likely blown:

  • Muffled or fuzzy distortion while playing music
  • Buzzing instead of music (note that buzzing when the volume is off is a different problem)
  • Hissing or crackling while playing music
  • Any of the above sounds at specific ranges of sound depending on the type of speaker
  • No sound at all (note that there could be other reasons that your speakers aren't working at all though)

What Causes Speakers to Blow?

There are a number of reasons why speakers blow. The most common in our opinion are distortion, heat, and deterioration. But in general, anything that could that damages a speaker can cause it to blow or not work properly.

Distortion is the most common reason a speaker fails. This is because distortion can be caused by many things. Here's a quick list of things that can cause distortion. You'll know a few already:

  • Too much power – When you've amplified speakers and given them too much power, more than they're rated for at least, it can cause the speakers to perform at a level that they can't handle.
  • Too little power – When there's not enough power, the speakers actually distort more than they do with too much power just at lower volumes. You might try to crank up the tunes but if the speakers don't have the power they could distort and cause failure.
  • Sound frequency is out of the recommended range – Speakers come with a frequency range that's optimized for the amount of surface area that they have. The best way to understand this is to picture using a tweeter to emit bass (extreme example I know). But you get the picture. When you do this, it causes the speaker to try to reproduce sounds that it's mechanically not capable of doing and distorts.

In all three cases, the failure from distortion is mechanical. When the speaker's cone is forced to move in ways that it was not designed to move. The result is stretched, stressed materials that collide with other materials in the speaker frame causing permanent damage to the speaker's components.

Speakers also can ‘blow' from heat though. This can also be caused by overpowering your speakers. When you send too much power to the speakers (by turning up the volume on your car stereo), they build up more heat than they can handle. The heat softens the adhesive that holds components together and might even melt other key components like the voice coil. Ultimately, something gives due to the heat and the speaker fails. In cases where your speaker no longer works at all, it's likely from overheating.

Deterioration is something that you really don't think about unless it happens. All materials deteriorate, some faster than others. The most common form of deterioration that causes speaker failure is the rubber component that surrounds the speaker cone. When this deteriorates, it throws material inside and outside of the speaker and cause the speaker to sound distorted or crackle. Other forms of deterioration include oxidization of coils and terminals and speaker frame, and dried/breakage of the cone itself.

What to Do About Blown Speakers

Now that you know what a blown speaker sounds like and what may have caused it, you can move forward with fixing the problem. In some cases, you might be able to fix a blown speaker. Like a dented cone or oxidized terminal. But in most cases it just isn't worth it. An aged or broken speaker is more likely to break in the future. Replacement is the obvious solution but there's a few things you'll need to do in order to replace them. The first thing to do is to find out what size speakers you're going to be replacing. We recommend using Metra's fitment guide on the bottom right hand side of the page here.

Once you've found out what size speaker you'll be replacing you'll need to find the right speaker. You'll also want to evaluate what caused them to blow in the first place. Make sure you're finding speakers that align with the power ratings of the vehicle's other components, like amplifier or head unit. We've put together recommendations of car speakers of all sizes, for example 6×9 speakers. But remember, just because you have the best speakers doesn't mean they won't blow. Make sure you find the speaker that best matches your needs and aligns with your other stereo components.