Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Installing VLC Media Player voids your speaker warranty

en.community.dell.com

Post reply on HN
Print view View original

51–60 of 224 posts

Re: Installing VLC Media Player voids your speaker warranty

#51

Post by anaphor »

ksec wrote: post #45
jbk wrote: post #15

As the main developer of VLC, we know about this story since a long time, and this is just Dell putting crap components on their machine and blaming others. Any discussion was impossible with them. So let me explain a bit... In this case, VLC just uses the Windows APIs (DirectSound), and sends signed integers of 16bits (s16) to the Windows Kernel. VLC allows amplification of the INPUT above the sound that was decoded…

Arh, I remember all sort of speaker problem ages ago. Never got around to figure what was wrong. I suppose this is it. But does anyone have list of Manufacture that does provide speaker with BIOS Protection?. Does Apple do?

How would that work? Just detect signals with an abnormally high RMS and block them?

Re: Installing VLC Media Player voids your speaker warranty

#52

Post by guard-of-terra »

ferongr wrote: post #47
jbk wrote: post #15

As the main developer of VLC, we know about this story since a long time, and this is just Dell putting crap components on their machine and blaming others. Any discussion was impossible with them. So let me explain a bit... In this case, VLC just uses the Windows APIs (DirectSound), and sends signed integers of 16bits (s16) to the Windows Kernel. VLC allows amplification of the INPUT above the sound that was decoded…

While I don't support Dell's decisions, digital (and analog) clipping can easily damage speakers driven at what is normally their maximum power they can handle, since the resulting clipped waveform carries a lot more energy than an unclipped one.

Nobody prevents the manufacturing to put some electronic bits before the speakers to cap the maximum power. Even better, teach the sound card to do that.

Re: Installing VLC Media Player voids your speaker warranty

#53

Post by GeneralMayhem »

donatj wrote: post #13

VLC is incapable of increasing the actual power past 100%, all that is being done is the waveform is being modified to be louder within the allowed constraints. If this wrecks the speaker, any other non-VLCed sound could just as easily, and the speakers are therefore underpowered for the laptops internal amplifier. Class action sounds in order.

Class action, and also direct action on the part of VLC for slander (if the VLC project is in a position to have lawyers available).

Re: Installing VLC Media Player voids your speaker warranty

#54

Post by anaphor »

donatj wrote: post #13

VLC is incapable of increasing the actual power past 100%, all that is being done is the waveform is being modified to be louder within the allowed constraints. If this wrecks the speaker, any other non-VLCed sound could just as easily, and the speakers are therefore underpowered for the laptops internal amplifier. Class action sounds in order.

Also many mastering engineers do the exact same thing to make the music "louder" because the record label/artists demand it. Maybe Dell should start making popular rock/pop music void the warranty as well.

Re: Installing VLC Media Player voids your speaker warranty

#55

Post by patcheudor »

mertd wrote: post #42
brador wrote: post #36

Earlier quoted context omitted.

How about detecting Dell Speakers and automatically setting the max volume to 100%, with a notification so the user can give an a-ok if they want to go higher. That way, at least users know and can make a decision. Similar to the Android warning if you set your volume too high that it could cause hearing damage. I'd prefer to be warned rather than surprised by this!

That's impractical. VLC is just using the standard OS API to send some sound to speakers. Can you imagine every piece of software checking for every piece of esoteric hardware and having some special behavior? Maybe Microsoft could regulate the output for junk speakers, but really, Dell is the one to blame here.

Impractical and impossible are of course two different things. It's sort of funny to consider a scenario in which a manufacturer adds a thermistor to the speaker coil assembly to measure the temperature & lower the amplifier output via the BIOS as the temperature in the voice coil rises to a dangerous level. I suspect that might cost more than using good speakers in the first place but then again if there's limited room for speakers which would lead to heat buildup in the voice coil such a solution might be practical.

Re: Installing VLC Media Player voids your speaker warranty

#56

Post by ferongr »

guard-of-terra wrote: post #52
ferongr wrote: post #47

Earlier quoted context omitted.

While I don't support Dell's decisions, digital (and analog) clipping can easily damage speakers driven at what is normally their maximum power they can handle, since the resulting clipped waveform carries a lot more energy than an unclipped one.

Nobody prevents the manufacturing to put some electronic bits before the speakers to cap the maximum power. Even better, teach the sound card to do that.

Analog limiter ICs (that I know of) limit the signal according to input voltage, something that does not catch this issue. Furthermore, limiting power at the audio codec level would require for the codec to have that feature and I don't know of audio codecs with that capability.

Re: Installing VLC Media Player voids your speaker warranty

#57

Post by orik »

mansr wrote: post #32

When the Samsung ARM Chromebook came out, people quickly found that careless tinkering with alsamixer caused the speakers to overheat and melt the case as a result of being driven with a high DC current. A driver update blocked the control causing the damaging signal routing.

I never realized they fixed that! What great news!

Re: Installing VLC Media Player voids your speaker warranty

#58

Post by lutusp »

jbk wrote: post #15

As the main developer of VLC, we know about this story since a long time, and this is just Dell putting crap components on their machine and blaming others. Any discussion was impossible with them. So let me explain a bit... In this case, VLC just uses the Windows APIs (DirectSound), and sends signed integers of 16bits (s16) to the Windows Kernel. VLC allows amplification of the INPUT above the sound that was decoded…

> The issue here is that Dell sound cards output power (that can be approached by a factor of the quadratic of the amplitude)

This is correct, and for those who want to know the technical reason, we can look at the Dell speakers (any speakers) as a resistive load (only approximately true). For a resistive load, the power increases as the square of the applied voltage, because the power in a resistor is equal to the voltage times the current, and both the voltage and current are increasing as the audio output level is increased.

In terms of Ohm's Law: P = E^2/R.

Re: Installing VLC Media Player voids your speaker warranty

#59

Post by dzhiurgis »

jbk wrote: post #15

As the main developer of VLC, we know about this story since a long time, and this is just Dell putting crap components on their machine and blaming others. Any discussion was impossible with them. So let me explain a bit... In this case, VLC just uses the Windows APIs (DirectSound), and sends signed integers of 16bits (s16) to the Windows Kernel. VLC allows amplification of the INPUT above the sound that was decoded…

Someone should upload video to YouTube with high gain and call it: "This video will void your Dell laptop speaker warranty" :)

Re: Installing VLC Media Player voids your speaker warranty

#60

Post by lutusp »

DrJokepu wrote: post #40
brador wrote: post #36

Earlier quoted context omitted.

How about detecting Dell Speakers and automatically setting the max volume to 100%, with a notification so the user can give an a-ok if they want to go higher. That way, at least users know and can make a decision. Similar to the Android warning if you set your volume too high that it could cause hearing damage. I'd prefer to be warned rather than surprised by this!

Assuming the speakers are connected through an audio jack, is there a realiable way of detecting specific speaker models?

The problem being discussed is by no means limited to Dell speakers -- it would be a problem for any small laptop speakers connected to an IC that can overdrive them under specific circumstances.
Post reply on HN