What does it sound like when you "blow" a speaker?

M

MeAgain

Carbonite Member
This isn't really a pressing matter, I was messing around in a sound editor and wanted to see how many processed tracks my PC could handle at once. I totally forgot about, you know, adjusting the volume or the fact that it wasn't muted and played about 20 voices tracks at once on my very crappy internal speaker, which isn't very powerful, needless to say. After the distorted mess started playying, I stopped it. Afterwards I noticed every time I played something- a song, sound file, whatever- on the internal speaker, it was very heavily distorted. However, with headphones or external speakers, the sound is fine. I assume I messed up the internal speaker? And if so, I'm wondering what the actual physical action was that happened to fry it.
 
speakers are a coil enclosed into a magnet.
one end of the coil is linked to some material to make a moving surface (the cone or membrane) to vibrate air. the shockwave of vibrating air against your ear make you tympanon to vibrate, so that is what we call sound.
When you apply AC voltage to the coil, it moves into the magnet back and forth and it gets hot too.
if you apply to much power to the coil, you can make it burn (totally=no more sound) or partially (distorded coil causing friction into the magnet). Some very hitech material can also brake (especially in tweeters). Less probably you can make the coil pop up out of the magnet or crash into the magnet, this causing aslo distorded coil.
if you still get sound but distorted, it means the structure of loudspeaker is damaged and you have to change it.
http://www.google.com/imgres?imgurl=http://i4.ytimg.com/vi/KErbjC98yoM/default.jpg&imgrefurl=http://www.youtube.com/watch%3Fv%3Dr9weTX6_1JY&usg=__bSesXK-Gl02JTTkfEbsytZ2gaYc=&h=90&w=120&sz=2&hl=en&start=132&itbs=1&tbnid=AHyhzzvhFiaNdM:&tbnh=66&tbnw=88&prev=/images%3Fq%3Dburned%2Bloudspeaker%26start%3D120%26hl%3Den%26sa%3DN%26gbv%3D2%26ndsp%3D20%26tbs%3Disch:1
 
Last edited:
Over-excursioning can sometimes be fixed by gentle application of a finger. Digital distortion produces almost DC on spikes and clicks. Small speakers, with very soft surrounds attaching the cone to the chassis basket, can pop the coil out of it's groove. The sound after this is thin, nasty and unpleasant - if it makes a noise at all! Gentle outwards pressure then a slow circular movement with your finger could well pop it back. Getting to the speakers will be the biggest problem.
 
I suspect in your case that is was not a matter of overpowering your speaker, but rather a case of increased duty cycle as a result of overdriving the speaker's amplifier, and the amplifier then sent a clipped signal to the speaker resulting in a increased duty cycle. As others have explained, the voice coil is the driver which converts energy into motion. The back and forth motion is used as a means of cooling the voice coil. When the amplifier clips, the waveform is distorted into a more square shaped wave. The rise time, both in the negative and positive polarity increases sharply, forcing the voice coil more agressively (risetime) with each cycle.

The result is the same as burning a voice coil with too much power. The cylindrical windings become overheated, causing the insulation (typically a varnish-like substance) to burn, become scaly or blistering to the point where these "burrs" drag along the gap in the magnet, causing the coil to "stick" as it travels back and forth. Sometimes it gets stuck completely. The result is a scratchy, distorted sound since the speakers compliance is now totally out of whack as the result of the friction.

It happens when working with lots of audio. Sometimes I've hammered my Event TR6s and cringled at the possibility that I had hurt them.

Anyway, that's what I think.
 
Last edited:
Well, it still works OK, but now everything has a kind of warbley buzz behind it, especially on lower tones. I guess it got part-way damaged. It's not a big deal, it just isn't my computer and I felt a little bad. Thankfully the owner didn't care since it's an old computer and a crappy internal speaker...and I'm very glad it was that that got fried and not me wearing my headphones...
 
It sounds like opening your wallet and slapping down a credit card...

Oh internal speaker. Same sound but you can probably do it with what's in the bill section.
 
It is super simple to open up a PC, remove the speaker and pop in a new one. Even if it is specific to the case you can go to the local radio shack (hurry before they go bankrupt) and procure a new generic one.
 
You must log in or register to reply here.
Back
Top