Sounding like New Again: Fixing or Replacing a Blown Speaker
A blown speaker is one of the worst things that could possibly happen to your audio rig. You might not know if you can fix your blown speaker or if you need to replace the speaker.
Keep reading to learn what you should do if you are dealing with a blown speaker and if you should replace it or if you can fix it.
How Blown Speakers Happen
Speakers blow due to two things either thermal or mechanical failure.
Mechanical failure happens it’s because of the over-excursion of the cone of the speaker. This is when the cone moves too far beyond it’s limited to the point that it gets damaged because of too much power frequencies that are too low.
Mechanical failure shows that the voice coil is tearing away from the cone, and the voice coils move too far that it hits the rear plate. Sometimes you can even hear it click when it hits. Or the surround is getting over-worked and breaks down.
Thermal failure can happen because of excessive power heating on the voice coil. This causes the varnish of the coil wire to turn black, exposing the wire to shirting and even melting away at the wires. Either way, this will make the speaker perform poorly,
Is Your Speaker Blown?
Your speaker might not be working, but is it blown? If you have a thermal failure you can actually smell the damage. The burnt varnish will smell distinctly burnt. Typically you can follow your nose with this.
You also can remove the grill and lightly push in the speaker’s cone to release it. Do not force the cone, if it doesn’t move freely. If it feels like there is spring tension from the surround then the speaker might be fried.
If there is a mid-frequency driver or a form of a paper tweeter, there might not be much movement to start with, and moving the cone won’t tell you much. Also while you are pushing you might hear or feel a scratching or scraping.
Aside from preventing winding to winding shots, the coil wire’s varnish also keep the wires in coil form. If the varnish has melted away on the coil, it can become loose, rubbing the walls of the magnet gap.
This would not show the damage, but you would push the cone sideways. You might also find that your speaker is working, it just sometimes cuts in and out. This could be because of melted coil wires that are shorting to the gap or broken wire that is making contact with the coil get moved by the music.
Mechanical damage usually doesn’t fully stop the speaker from working, unless it goes unnoticed for longer. When a speaker bottoms out with large power and low-frequency peals, this could damage the speaker causing it to totally stop.
However, most mechanical damage has a loss of performance that is noticed before the sound is heard. The more speakers you have in your system, the less likely you are to notice that one is getting abused.
You should remember there is a crossover, speaker cable, jacks, internal wires and sometimes many connections between the actual speaker and the power amp. You will need to examine these items, especially if you don’t have obvious visual wear and tear, or there’s a smell.
You’ll want to test your cable out on working cabinets, if you are savvy and can dig in, you should check the connections. If you have two of the same cabinets, then you can swap the crossovers to test this more.
You might even want to look over the crossover for a broken solder, missing parts, burnt or loose connections. Lastly, do not void the warranty.
There are free warranty repairs so check that first, and don’t be afraid to talk to customer service. Often they can walk you through some checks that will make the fix happen faster.
Replace Or Recone?
Now, the big question: should you replace your speaker or can you fix it? If your speaker is dead in the water, you can either replace or recone it.
Reconing A Speaker
Reconing is a process where all the moving parts including the surround, voice coil, and cone are replaced. It’s a tricky process that should be done by an experienced professional. Some manufacturers will offer recone kits if you want to try it yourself.
If you recone the speaker properly, then it’s good as new. For rare and or vintage speakers, reconning is the only option, since that speaker is likely no longer available for purchase.
Replacing the Speaker
If you replace the speaker you should know that standard guitar cabinets without a passive crossover will typically change the speaker to another guitar speaker without any issues.
This is usually done for tone changes and so you can find your sound. Keep in mind that the guitar head was likely designed to use the original speaker so it might not sound as good with the speaker. If you have a bass guitar or PA cabinets, you will want your new speaker to be replaced with the original specified ones or whatever the recommended alternative is.
Different from a guitar cabinet, there is more low frequency and multi drivers involved. So the speaker is the key part of the crossover and cabinet design. An off-spec model will not only change the sound, but it also might not perform as well and could lead to another mechanical issue.
Higher power speakers are not designed for cabinet tuning, and can easily fail at lower power. So if you enjoyed how the cabinet used to sound, you might not like these results.
Fix Your Speaker
Now that you know what to do with a blown speaker, fix or replace your speaker. Your speaker has either suffered thermal or mechanical failure, and you will have to decide if you can recone it, or if you will have to replace it.