13 ms·

Can YOU blow a PC speaker using only a Linux kernel driver?

jancsika 5y ago
What would happen if you sent a random stream of ones and zeros to the PC speaker? Wouldn't that be equivalent to the PC speaker producing square waves at all the frequencies which it can produce? At least if wearing it out in the fastest manner possible counts as "blowing" it, that could work...
- schaefer 5y ago
  In the late 90s and early 2000s, I remember two distinct occasions where a computer tried to play a data cdrom as if it where an audio CD through my headphones. Easily one of the more unpleasant experiences of my life (and I’ve broken bones). Something about the sound triggered a very specific Synesthesia. I smelled a burning smell for half a day. So… in addition to blowing speakers, you can also blow minds.
  - yjftsjthsd-h 5y ago
    So the takeaway here is that you should not attempt to fuzz a human brain while using it:)
mcraiha 5y ago
Related, VLC Media Player destroyed Dell speakers thread https://www.dell.com/community/Laptops-General-Read-Only/VLC-Media-Player-WARNING/td-p/4082242 https://www.dell.com/community/Laptops-General-Read-Only/VLC...
- jolmg 5y ago
  I wouldn't blame VLC. Here's the response from main VLC developer: https://news.ycombinator.com/item?id=7205875 https://news.ycombinator.com/item?id=7205875 I agree with them that when using the official API for whatever-X, you can't be blamed when X fails. Whatever X is, it should be built to cover all uses of its official interface. In the case of VLC, that X is the Dell sound hardware, which can't handle certain uses because of a power incompatibility between the Dell sound card and the Dell speakers. Reminds me of a case long ago where a GUI program took blame because it sometimes caused the X11 server to crash. That was clearly a bug on the X11 server side, too. A server should be built such that it's impossible for a client to crash it.
  - kevingadd 5y ago
    I always get a little nervous when really messed up audio gets sent through my semi-expensive speakers... "are they designed for this? did I just ruin them by playing a game with a buggy audio mixer?"
    - jolmg 5y ago
      The audio mixer is dependent on the speakers, not the other way around. The speakers should be able to handle anything the mixer is able to throw at it. If they aren't, that's fault on the speakers' part.
      - bob1029 5y ago
        I think this is a grey area depending on your setup and listening preferences. I have ~2kW of RMS amplification available to my floorstanding loudspeakers and subwoofer. There is a lot of DSP/EQ protection in between my HTPC and the mechanical drivers in the speakers. Despite all of this, I have had incidents where the software glitches out and plays the un-decoded DTS/DD stream. If you have your volume set at or near reference when something like this happens, it can cause physical damage (to both your speakers and your ears). (Audio) Engineering is all about balancing many complex factors. Mistakes happen and you can't address all of the edge cases without ruining the overall user experience. To say its the fault of the speaker is a little bit accusatory in my opinion. Can you ruin your car by taking certain actions? Certainly. Is this the car's fault? No.
        deleted 5y ago
        [deleted]
        nitrogen 5y ago
        To add to this, depending on the amplifier design you might get better linearity (less harmonic distortion) by significantly overprovisioning power.
        deleted 5y ago
        [deleted]
timw4mail 5y ago
Now I wonder if a piezo beeper would be more plausible or less plausible to blow?
- capableweb 5y ago
  PC Speakers commonly are piezo beepers, but that's probably "recent".
  - timw4mail 5y ago
    Well yes, but peizo beepers were much less common when the PC speaker was commonly used for games, or just as the main sound output.
    - Someone 5y ago
      Reference: https://en.wikipedia.org/wiki/PC_speaker https://en.wikipedia.org/wiki/PC_speaker
- londons_explore 5y ago
  piezo beepers typically have a resonance frequency where they are much louder. Run it at that frequency for too long and the pizeoelectric coating delaminates from the metal disc of the speaker, leading to failure. So, yes, you can probably blow them from software if you're willing to have it turned on for a few days continuously.
  - timw4mail 5y ago
    I wonder if moving iron beepers would have the same issue. Either way, seems like a lot of effort.
frostyiguana 5y ago
All I can say in my early Linux years is I tried to redirect /dev/cpu to my speakers (maybe something in /dev/snd), and it made one of the loudest sound my quite huge speakers could make. and volume wasn't so high.. I tried that because I was curious, since everything is a file, then surely cpu processing things to become a sound right ? :) (if you try this please make sure to get that into a pcm/wav file, and reduce the amplitude of that file _first_)
- carrja99 5y ago
  lol I did this too eons ago. I don't think those speakers ever worked the same again after that.
throwaway789657 5y ago
Why don't all speakers have some circuitry that blocks any signal that could blow out the speakers? This has always seemed like an absurd state of affairs. It should not be possible to damage speakers by turning the volume too loud.
- londons_explore 5y ago
  Because knowing exactly how much signal is too much is really hard. When using the speaker, for some purposes you want absolutely max volume - that involves getting the physical parts of the speaker moving fast and far. Yet move them slightly too fast or too far or do that too often and it'll physically break. Odd effects like resonance mean two very similar looking signals can have widely different physical effects. The ideal threshold might depend on numerous factors, like temperature and pressure, the age of the speaker, etc. Easy to do in software, impossible in hardware. So why not just have more margin and make the line between 'loud enough' and 'breaking apart' wider? Well to do that your speaker would need to be physically larger, and space is very much in a premium in many devices.
  - throwaway789657 5y ago
    In no other high-end consumer product would that unreliability be tolerated. Why would you ever run your speakers at a volume that might blow them out depending on what the next bar of the song sounds like? Are you pre-screening every single bit of audio that will get played over your speakers? Otherwise, you should never run speakers at a borderline volume. This protection should be built in to the speaker. No matter how much volume you feed into a speaker, it should not break. (Of course, you could feed always feed such an absurd amount of power that it would break even the protective circuits, but that ultimate vulnerability is just inherent in the nature of electronics).
    - walshemj 5y ago
      It happens with DJ sound systems and Band PA's
yrral 5y ago
Related: In the past Apple released a bad bootcamp sound driver for macbooks that caused windows to blow the laptop speakers. So technically you can blow some speakers with bad drivers https://www.extremetech.com/computing/240309-apples-bootcamp-audio-driver-can-permanently-damage-speakers-new-macbook-pro https://www.extremetech.com/computing/240309-apples-bootcamp... https://forums.macrumors.com/threads/15-2016-mbp-speaker-crackling.2015467/ https://forums.macrumors.com/threads/15-2016-mbp-speaker-cra... https://www.reddit.com/r/apple/comments/5e1g37/warning_bootcamp_driver_causing_blown_speakers_in/ https://www.reddit.com/r/apple/comments/5e1g37/warning_bootc...
- hutattedonmyarm 5y ago
  The article seems to be about those tiny PC speakers which beep out BIOS codes, not those types of speakers used to output actual OS sounds and music
dlevine 5y ago
This reminds me of Godel Escher Bach. “I Cannot Be Played on PC Speaker X.”
anonymousisme 5y ago
One possible way to approach this would be to write a simple function generator (square wave) and sweep it across the audio spectrum, while also recording the speaker output level by way of a connected microphone. The resonant frequency of the speaker (or the microphone) should be observable as the peak amplitude seen by the mic. Once known, just set the generator to that frequency and blast away for a while.
EamonnMR 5y ago
I've definitely blown PC speakers with softsynths before so it should be possible in principle.
squarefoot 5y ago
The PC speaker was driven by square waves, therefore there was no way to alter the audio volume, or change its sound. Only frequency could be altered, literally by inverting the pin status N times a second. Then it came the PWM idea, and hackers found the way to implement analog sounding audio through it (the same principle used to fade a led through a GPIO). The port became a DAC, audio levels were encoded through PWM, and the speaker inertia made for a crude but effective Nyquist-like filter. Having full hardware access to the port, the nastiest thing one could do is to keep the speaker on fixed DC by setting the port to a digital value (that is, 1 or 0) and never changing it. PWM ensures that sometimes the speaker isn't driven, which reduces the average current, and therefore the load from the driver perspective, but now we're making current flow through it continuously. Will that destroy it? I don't know, but to my knowledge it seems the only way one can abuse it, or the port that drives it. It all boils down to current limiting circuitry; if it's present, then I guess there's no way to damage either the speaker or the driving port.
simonblack 5y ago
Whether or not you can blow a speaker has nothing to do with what kind of signal you are sending it but the power you send to the speaker. In other words, whether the current going through the speaker is sufficient to either overheat the voice-coil, or to drive the speaker-cone beyond its physical limits. These are qualities pertaining to the speaker itself, not the PC's output. The easy answer to the question is "It depends".
- boredprograming 5y ago
  Excursion is related to frequency. A sure way to blow most up is turn bass to the max. Some speakers have bandpass filters. Cheap ones usually don't
justinclift 5y ago
VLC can, for some specific models of Dell laptop: https://hardware.slashdot.org/story/14/02/09/1828229/customer-dell-denies-speaker-repair-under-warranty-blames-vlc https://hardware.slashdot.org/story/14/02/09/1828229/custome... Also https://news.ycombinator.com/item?id=7205759 https://news.ycombinator.com/item?id=7205759 In short, Dell sold laptops a few years ago where the included speakers weren't specc-ed out right. So, Dell was blaming VLC and other applications for destroying the speakers, when it was just Dell's bad choice of shitty components.
woliveirajr 5y ago
A long time ago there were a _consensus_ that no driver could break hardware in a physical way. Then I wrote a small asm that moved the FDD heads way past the last track and it stoped working (couldn't move the head back to regular position anymore). And, despite all arguments, I kept my opinion. Then Stuxnet came and now this discussion is over.

Can *YOU* blow a PC speaker using only a Linux kernel driver?

What would happen if you sent a random stream of ones and zeros to the PC speaker? Wouldn't that be equivalent to the PC speaker producing square waves at all the frequencies which it can produce? At least if wearing it out in the fastest manner possible counts as "blowing" it, that could work...

schaefer 5y ago
In the late 90s and early 2000s, I remember two distinct occasions where a computer tried to play a data cdrom as if it where an audio CD through my headphones. Easily one of the more unpleasant experiences of my life (and I’ve broken bones). Something about the sound triggered a very specific Synesthesia. I smelled a burning smell for half a day. So… in addition to blowing speakers, you can also blow minds.
- yjftsjthsd-h 5y ago
  So the takeaway here is that you should not attempt to fuzz a human brain while using it:)

mcraiha 5y ago

Related, VLC Media Player destroyed Dell speakers thread https://www.dell.com/community/Laptops-General-Read-Only/VLC-Media-Player-WARNING/td-p/4082242 https://www.dell.com/community/Laptops-General-Read-Only/VLC...

jolmg 5y ago
I wouldn't blame VLC. Here's the response from main VLC developer: https://news.ycombinator.com/item?id=7205875 https://news.ycombinator.com/item?id=7205875 I agree with them that when using the official API for whatever-X, you can't be blamed when X fails. Whatever X is, it should be built to cover all uses of its official interface. In the case of VLC, that X is the Dell sound hardware, which can't handle certain uses because of a power incompatibility between the Dell sound card and the Dell speakers. Reminds me of a case long ago where a GUI program took blame because it sometimes caused the X11 server to crash. That was clearly a bug on the X11 server side, too. A server should be built such that it's impossible for a client to crash it.
- kevingadd 5y ago
  I always get a little nervous when really messed up audio gets sent through my semi-expensive speakers... "are they designed for this? did I just ruin them by playing a game with a buggy audio mixer?"
  - jolmg 5y ago
    The audio mixer is dependent on the speakers, not the other way around. The speakers should be able to handle anything the mixer is able to throw at it. If they aren't, that's fault on the speakers' part.
    - bob1029 5y ago
      I think this is a grey area depending on your setup and listening preferences. I have ~2kW of RMS amplification available to my floorstanding loudspeakers and subwoofer. There is a lot of DSP/EQ protection in between my HTPC and the mechanical drivers in the speakers. Despite all of this, I have had incidents where the software glitches out and plays the un-decoded DTS/DD stream. If you have your volume set at or near reference when something like this happens, it can cause physical damage (to both your speakers and your ears). (Audio) Engineering is all about balancing many complex factors. Mistakes happen and you can't address all of the edge cases without ruining the overall user experience. To say its the fault of the speaker is a little bit accusatory in my opinion. Can you ruin your car by taking certain actions? Certainly. Is this the car's fault? No.
      - deleted 5y ago
        [deleted]
      - nitrogen 5y ago
        To add to this, depending on the amplifier design you might get better linearity (less harmonic distortion) by significantly overprovisioning power.
      - deleted 5y ago
        [deleted]

timw4mail 5y ago

Now I wonder if a piezo beeper would be more plausible or less plausible to blow?

capableweb 5y ago
PC Speakers commonly are piezo beepers, but that's probably "recent".
- timw4mail 5y ago
  Well yes, but peizo beepers were much less common when the PC speaker was commonly used for games, or just as the main sound output.
  - Someone 5y ago
    Reference: https://en.wikipedia.org/wiki/PC_speaker https://en.wikipedia.org/wiki/PC_speaker
londons_explore 5y ago
piezo beepers typically have a resonance frequency where they are much louder. Run it at that frequency for too long and the pizeoelectric coating delaminates from the metal disc of the speaker, leading to failure. So, yes, you can probably blow them from software if you're willing to have it turned on for a few days continuously.
- timw4mail 5y ago
  I wonder if moving iron beepers would have the same issue. Either way, seems like a lot of effort.

frostyiguana 5y ago

All I can say in my early Linux years is I tried to redirect /dev/cpu to my speakers (maybe something in /dev/snd), and it made one of the loudest sound my quite huge speakers could make. and volume wasn't so high.. I tried that because I was curious, since everything is a file, then surely cpu processing things to become a sound right ? :) (if you try this please make sure to get that into a pcm/wav file, and reduce the amplitude of that file _first_)

carrja99 5y ago
lol I did this too eons ago. I don't think those speakers ever worked the same again after that.

throwaway789657 5y ago

Why don't all speakers have some circuitry that blocks any signal that could blow out the speakers? This has always seemed like an absurd state of affairs. It should not be possible to damage speakers by turning the volume too loud.

londons_explore 5y ago
Because knowing exactly how much signal is too much is really hard. When using the speaker, for some purposes you want absolutely max volume - that involves getting the physical parts of the speaker moving fast and far. Yet move them slightly too fast or too far or do that too often and it'll physically break. Odd effects like resonance mean two very similar looking signals can have widely different physical effects. The ideal threshold might depend on numerous factors, like temperature and pressure, the age of the speaker, etc. Easy to do in software, impossible in hardware. So why not just have more margin and make the line between 'loud enough' and 'breaking apart' wider? Well to do that your speaker would need to be physically larger, and space is very much in a premium in many devices.
- throwaway789657 5y ago
  In no other high-end consumer product would that unreliability be tolerated. Why would you ever run your speakers at a volume that might blow them out depending on what the next bar of the song sounds like? Are you pre-screening every single bit of audio that will get played over your speakers? Otherwise, you should never run speakers at a borderline volume. This protection should be built in to the speaker. No matter how much volume you feed into a speaker, it should not break. (Of course, you could feed always feed such an absurd amount of power that it would break even the protective circuits, but that ultimate vulnerability is just inherent in the nature of electronics).
  - walshemj 5y ago
    It happens with DJ sound systems and Band PA's

yrral 5y ago

Related: In the past Apple released a bad bootcamp sound driver for macbooks that caused windows to blow the laptop speakers. So technically you can blow some speakers with bad drivers https://www.extremetech.com/computing/240309-apples-bootcamp-audio-driver-can-permanently-damage-speakers-new-macbook-pro https://www.extremetech.com/computing/240309-apples-bootcamp... https://forums.macrumors.com/threads/15-2016-mbp-speaker-crackling.2015467/ https://forums.macrumors.com/threads/15-2016-mbp-speaker-cra... https://www.reddit.com/r/apple/comments/5e1g37/warning_bootcamp_driver_causing_blown_speakers_in/ https://www.reddit.com/r/apple/comments/5e1g37/warning_bootc...

hutattedonmyarm 5y ago
The article seems to be about those tiny PC speakers which beep out BIOS codes, not those types of speakers used to output actual OS sounds and music

dlevine 5y ago

This reminds me of Godel Escher Bach. “I Cannot Be Played on PC Speaker X.”

anonymousisme 5y ago

One possible way to approach this would be to write a simple function generator (square wave) and sweep it across the audio spectrum, while also recording the speaker output level by way of a connected microphone. The resonant frequency of the speaker (or the microphone) should be observable as the peak amplitude seen by the mic. Once known, just set the generator to that frequency and blast away for a while.

EamonnMR 5y ago

I've definitely blown PC speakers with softsynths before so it should be possible in principle.

squarefoot 5y ago

The PC speaker was driven by square waves, therefore there was no way to alter the audio volume, or change its sound. Only frequency could be altered, literally by inverting the pin status N times a second. Then it came the PWM idea, and hackers found the way to implement analog sounding audio through it (the same principle used to fade a led through a GPIO). The port became a DAC, audio levels were encoded through PWM, and the speaker inertia made for a crude but effective Nyquist-like filter. Having full hardware access to the port, the nastiest thing one could do is to keep the speaker on fixed DC by setting the port to a digital value (that is, 1 or 0) and never changing it. PWM ensures that sometimes the speaker isn't driven, which reduces the average current, and therefore the load from the driver perspective, but now we're making current flow through it continuously. Will that destroy it? I don't know, but to my knowledge it seems the only way one can abuse it, or the port that drives it. It all boils down to current limiting circuitry; if it's present, then I guess there's no way to damage either the speaker or the driving port.

simonblack 5y ago

Whether or not you can blow a speaker has nothing to do with what kind of signal you are sending it but the power you send to the speaker. In other words, whether the current going through the speaker is sufficient to either overheat the voice-coil, or to drive the speaker-cone beyond its physical limits. These are qualities pertaining to the speaker itself, not the PC's output. The easy answer to the question is "It depends".

boredprograming 5y ago
Excursion is related to frequency. A sure way to blow most up is turn bass to the max. Some speakers have bandpass filters. Cheap ones usually don't

justinclift 5y ago

VLC can, for some specific models of Dell laptop: https://hardware.slashdot.org/story/14/02/09/1828229/customer-dell-denies-speaker-repair-under-warranty-blames-vlc https://hardware.slashdot.org/story/14/02/09/1828229/custome... Also https://news.ycombinator.com/item?id=7205759 https://news.ycombinator.com/item?id=7205759 In short, Dell sold laptops a few years ago where the included speakers weren't specc-ed out right. So, Dell was blaming VLC and other applications for destroying the speakers, when it was just Dell's bad choice of shitty components.

woliveirajr 5y ago

A long time ago there were a _consensus_ that no driver could break hardware in a physical way. Then I wrote a small asm that moved the FDD heads way past the last track and it stoped working (couldn't move the head back to regular position anymore). And, despite all arguments, I kept my opinion. Then Stuxnet came and now this discussion is over.