Careful car owners don’t take long to notice a change in the functioning of their car’s audio system. A slight change in a car stereo’s sound quality hints that something is not right. The problem of blown car speakers is among the most common reasons for sub-optimal sound quality.
Car speakers of any type can blow especially if they are old. However, most speakers blow out either due to careless usage or accidents. With regard to carelessness, car speakers that play music at extremely high volumes for long periods of time are more likely to blow out.
What causes car speakers to blow?
A car speaker can blow when either or both of these two failures happen: mechanical failure and thermal failure.
Mechanical car speaker failures occur when speaker components are forced to move in ways they are not designed for. The cone is the most affected part. Normally, the cone is supposed to move up to a certain level. But in some circumstances, such as when the volume is very high, this part is forced to move further than this level. The material making the cone is put under stress and it can easily tear or become loose and the speaker is blown.
Thermal failures in a car speaker occur when the system sends more power to the speaker than it can handle. The excess power leads to a buildup of heat. As a result, some of the components that are held in place by glue may become loose or detached. In some cases, the wires inside the voice coil can melt due to the heat. These occurrences result to blowing up of the speaker.
After understanding how a car speaker blows, you can know how to diagnose blown car speakers because you have an idea of the damage you are looking for.
Types of blown car speakers
There are two types of blown speakers. Some speakers are completely blown while others partially blown.
When a speaker’s cone is completely separated from the coil, the speaker does not produce any sound at all. Such a speaker is completely blown.
Sometimes minor damages happen to some vital components of a car speaker. For instance, the midrange or tweeters can get damaged. The speaker produces sound though of low quality. Often, the sound is heavily distorted. Such a speaker is said to be partially blown.
How to diagnose blown car speakers
If you suspect that your car speaker is blown, there are various ways of ascertaining your suspicion. Here are simple methods you can use without expert knowledge to tell whether or not a speaker is blown:
- Listening to detect signs of speaker damage
For most people, this is the simplest thought that comes to mind when thinking of how to diagnose blown car speakers. You might have already done it in your own way but here’s the proper way of going about it.
- Turn on your car stereo. You want to reduce any other noise completely so make sure it’s only the stereo that is on and not the car’s engine. This is done by turning the start key halfway.
- Choose an audio track that you are familiar with, and one that has a full range of notes and a clear bass line.
- Play the music at high volume and make sure to equalize the bass and treble at a neutral position.
- Listen carefully to detect signs of speaker damage.
These are the signs you should be listening to detect:
- Sound distortion: A blown car speaker will produce a hiss that’s very easy to detect. The speaker may also be fuzzy with a muffled, crackling sound and this often signifies a damaged voice coil. These distortions increase when the volume is turned up.
- Incomplete range: Certain frequencies will be noticeably affected in a blown car speaker. If you are listening to a song that you know well, you will identify instances when certain mid, high and bass frequencies are altered consistently. This consistent alteration of frequencies is a sure sign of a blown speaker.
While still at the listening step, try to identify the exact speaker that is blown. You can do this through isolation of suspect speakers. The fader system controls on the car stereo’s head unit will help you isolate the speakers you think are damaged. Focus sound in one area of the car. If the overall sound fades partially or entirely, then you have found out the exact speaker that is blown.
- Diagnosing blown car speaker by touching
By simply placing your hand on the cone of a speaker, you can know whether or not it’s damaged. When a speaker is functioning properly, there are vibrations especially when the volume is turned up. If you can’t feel any vibration, it’s obvious that the cone isn’t receiving any power.
While this is not the most reliable way of how to diagnose blown car speakers, it’s a quick way of detecting malfunctioning car stereo components. It may also help to know when there is a wiring problem.
- Testing using a multimeter
With a multimeter, you can measure voltage, current, and resistance and identify a malfunctioning speaker. Turn off your car audio system and set the multimeter to read ohms. Place one meter lead on the speaker’s positive terminal and the other lead on the negative terminal. Check the reading on the multimeter and if it’s reading 1.0, the speaker is not damaged. If the meter reads infinite impedance, your speaker is blown.
Visual inspection of blown speaker
After identifying the blown speaker(s), the next step is determining the extent of the damage. Visual inspection suffices for this purpose and will inform your next move – whether to repair or replace the speaker. Most partially blown car speakers can be repaired but some completely blown ones are better replaced than repaired.
To perform a visual inspection, take off the speaker cover and look for tears, cracks, or holes on the cone. This is where most of the damage is usually found. If you cannot see any damages, use your fingers to gently push the cone at the edges to make sure there are no splits.
If there are no damages on the speaker’s cone, open up the voice coil to check the state of the wires. This is especially important if the speaker was not producing any sound at all. There could be a detached wire that’s preventing current from going through the speaker.
Knowing how to diagnose blown car speakers can save you a lot of time and money because you don’t have to contact a car stereo expert. Remember to take caution when working with electronics that are turned on as nasty shocks can occur. Also, handle wires with care to avoid short-circuiting the audio system. Otherwise, this knowledge puts you in a better position to solve one of the car stereo problems that disturb a significant number of drivers.