“Blown speakers” are quite widespread in the realm of home and automotive audio. Many people use the phrase in a non-technical, broad way to refer to loudspeakers that aren’t functioning properly or at all.
If you have a blown speaker, you may hear hiss, static, or fuzz. It may also present as lacking vibration. You can fix this by:
- Applying suction on the dust cap
- Using silicon rubber gel to repair tears
- Taping the indent
- Using the poke n’ pull technique
- Polarizing the wires
- Changing the fuse
Blown loudspeakers on a guitar amp (or bass amp, or PA system) are, however, much more than a minor nuisance for musicians – especially professional artists. They could pose a serious issue that jeopardizes a performance or a session. Luckily, it occurs much less frequently in musical instruments than it does in home and automobile audio, but when it does, it creates a number of issues.
Why Does the Speaker Blow Out?
Speaker blow-out often occurs when the speaker receives an excessive amount of signal for an extended period of time. Alternate currents with amplitudes measured in AC voltage are used to power speakers in sound systems. The voice coil of the speaker is intended to be a component of the circuit that transmits the signal.
Sound is produced by speakers by translating the electric current’s direction and amplitude into movement. The voice coil’s heat is dissipated as a result of this current.
Types of Speaker Blow-Out
Burnt Voice Coil
Typically, the speaker driver’s conductive portion dissipates heat.
The driver might not be able to adequately dissipate the heat, though, if the amplitude of the signal is too great. This can result in the conducting element melting or burning. The voice coil is the conductive component of moving-coil speaker drivers, which are currently the most popular.
If the coil is exposed to too much heat, it will basically melt into a big mass or perhaps get fused to the magnet. In the worst circumstances, this prevents the speaker from precisely replicating the audio signal or from even making any sound.
Torn or Stretched Cone/Suspension
When an elevated audio signal is provided, speaker drivers may occasionally become enlarged or ripped. If forced above its limit, the speaker driver will have a restricted range of movement and could stretch or rupture.
Nevertheless, it is improbable that straining a speaker with an elevated sound signal will cause the cone or driver suspension to expand or rupture.
Instead, when the driver exceeds its confinements of motion and starts to behave nonlinearly, the first thing that will occur is auditory disruption. Before the driver would likely be strained or torn, the voice coil would likely have melted or burnt as previously described.
The speaker could, though, suffer serious harm and become defected. The speaker may possibly be torn or stretched by foreign bodies and particles. Because of this, most speakers feature safety grilles or mesh.
The voice coil motion constraint in the X and Y axes will be removed by any tearing or excessive straining of the spider suspension inside the speaker driver. The driver’s magnetic field and housing will start to get bumped by and/or stuck to the loose voice coil. There is severe auditory disruption as a result of this blowout.
Older speakers’ materials may deteriorate to the degree where it seriously impairs their functionality.
However, it can also occur with other materials that experience erosion due to regular use. We frequently observe this with the foam-type surrounds and suspensions of earlier speaker designs.
Blown Fuse or Loose Wires
Electrical fuses are sometimes used in active loudspeakers and studio monitors to prevent speaker blow-out. The speaker cannot be powered on and may appear to be blown out if these fuses burst. The speaker could well be repaired while still being protected from high-amplitude auditory signals by changing this fuse.
Additionally, loose wiring can cause speaker burn-out, which manifests as disruption, crackle, and popping.
What Does a Blown Speaker Sound Like?
If you’re unsure whether your speakers are blown, following pointers might help:
If hiss, static, and fuzz are audible even at medium volume levels, you are likely dealing with one of two issues. You either have a ripped cone or you have a loose or broken voice coil. If you increase the volume level, the issue ought to get worse.
A speaker’s cone vibrates quickly to push air around and produce sound. Irrespective of volume level, if it’s not vibrating, it isn’t taking power. This indicates that either a cable has loosened, or a component of the speaker assembly isn’t working properly.
Rattles and Crackling Noises
In addition to the typical disturbance, you may also hear crackling sounds from burst tweeters, rattling from a cone fabric that is flopping, or sounds coming from an unstable voice coil.
For those who are more tech competent, you can measure the resistance at the voice coil using a multimeter. You certainly have an electrical issue on your hands if it’s almost limitless. In most situations, it should fall between 4 and 10 ohms.
Lastly, you can use the fader system to isolate the different speakers if you’re having difficulty determining which of your speakers is having problems. You will be able to identify the problematic speaker with ease as a result.
Additionally, you’ll be able to determine whether it is fully or partially blown. You might need to think about changing the speaker in both scenarios. You might need to manually unplug the speakers to examine them if you cannot use a fader system.
How to Fix Blown Speakers?
Of course, “Can you fix a blown speaker?” is usually the first query. You can, although doing it yourself isn’t usually advised.
However, if you’d still like to try out your options, you can test the following solutions and see if the problem gets resolved:
A dome or dust cap that has been punched in can frequently be gently “sucked out.” Generally speaking, this method of popping out an indentation is the best and safest. Many individuals use vacuum cleaner attachments for this, but you must be very careful to keep the intensity of pressure to a minimum.
To reduce the pressure, you can kink the hose or insert a piece of cloth, but in both cases, you must exercise extreme caution.
Use silicon rubber gel to repair any tears or separations between your cone and the cloth that surrounds it. Silicon must be used since it is elastic; else, you risk causing yet another rupture. This solution comes in tubes and may be purchased at any hardware shop.
Try to draw it out by applying adhesive tape to the indent while being cautious not to make it even worse. Use gentle sticky tapes, such as masking tape or scotch tape. The goal is to use the minimum degree of force necessary to complete the task. A stronger tape would be more likely to leave a film or damage the speaker.
Poke n’ Pull
The worst-case option for a tweeter dome or dust cap that has been improperly pushed in is “poke and pull.” In the case of a tweeter, it’s a terrible situation since, after all the poking, tugging, and patching, you’ll probably have a compromised speaker. Try to utilize materials that are similar to those used in the speaker cone itself when repairing.
Paper makes this simple because tissue and PVA glue can be used (yellow carpenters glue diluted with water).
Polarize speaker wires
Examine the speaker wires on the audio output gadget (CD player, stereo receiver, etc.) to ensure they are connected properly. The black terminal is [-] while the red terminal is [+] (negative). A comparable color code or other polarity preference indicator can be found on higher-quality speaker cables. If not, connect the two cables in any way, but ensure the [+] wire on the source is identical to the [+] wire on the rear of the speaker enclosure.
In a similar way, attach the wires to the speaker enclosure: [+] wire to [+] terminal, [-] wire to [-] terminal. As a result, the speaker will produce richer bass tones.
If the speaker has a blown fuse, changing it is a rather straightforward process. Replace the burnt fuse in the fuse box with a new one after removing the old one. Numerous active speakers and monitors include an additional fuse that is kept in a compartment close to the electrical outlet. Maybe a substitute fuse will need to be ordered.
The connecting wire linking the speaker drivers and their crossover network and/or amplifier may need to be replaced in order to fix loosened wires. The connections might also need to be re-soldered. Gently disassemble the speaker, then re-solder it if necessary.
Having a blown-out speaker can be really annoying. A lot of times people find it difficult to identify whether their speakers really are blown out. Luckily, there are ways you can check for blow-out and even some quick fixes that you can try yourself.