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Installing VLC Media Player voids your speaker warranty

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Re: Installing VLC Media Player voids your speaker warranty

#101

Post by tmzt »

lutusp wrote: post #95
KaiserPro wrote: post #79

Earlier quoted context omitted.

Thats what limiters are for. The whole point of hard clipping is that +256 or -256 (or the 16bit equivalent) is below the point at which your speakers, amps, cabling or anything else starts to melt. Speakers/amps should have DC protection builtin.

> Thats what limiters are for. Limiters cannot either distinguish or protect against the technical difference between a sine wave and a square wave: http://i.imgur.com/oE5NFZ9.png The red trace is a normal audio signal that doesn't exceed the dynamic range of the amplifier. The green trace is an example of the kind of signal one gets by turning the volume up way above normal. In a hypothetical speaker of one ohm and…

Couldn't he codec chip do it by averaging the amplitude? I'm not sure if they are more than a DAY though or whether they have a microcontroller and firmware.

Re: Installing VLC Media Player voids your speaker warranty

#102

Post by lutusp »

tmzt wrote: post #101
lutusp wrote: post #95

Earlier quoted context omitted.

> Thats what limiters are for. Limiters cannot either distinguish or protect against the technical difference between a sine wave and a square wave: http://i.imgur.com/oE5NFZ9.png The red trace is a normal audio signal that doesn't exceed the dynamic range of the amplifier. The green trace is an example of the kind of signal one gets by turning the volume up way above normal. In a hypothetical speaker of one ohm and…

Couldn't he codec chip do it by averaging the amplitude? I'm not sure if they are more than a DAY though or whether they have a microcontroller and firmware.

> Couldn't he codec chip do it by averaging the amplitude?

Yes in principle, but it would be rather complicated -- it would need to have its own microprocessor just to save the speaker. D/A ICs with included amplifiers are already pretty complex. Also, if a user was listening to music that had an occasional high level, the special limiter might kick in and spoil the sound of the audio for a transient that wouldn't actually jeopardize the speakers.

Re: Installing VLC Media Player voids your speaker warranty

#103

Post by svantana »

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.

True, but VLC actually applies soft limiting when set to above 100%, so that hard clipping never occurs. I use this feature alot, it's great for taking down the usually thunderous sound effects in hollywood movies a few notches, while keeping quiet scenes at hearable levels.

Re: Installing VLC Media Player voids your speaker warranty

#104

Post by slacka »

fnordfnordfnord wrote: post #28
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…

Low quality speakers and a poor hardware design. It isn't even a challenge to match amplifier output to speakers in such a way that the amplifier can't break the speaker. There are easily a dozen cheap ways to make this work properly that don't rely upon a probably non-existent WMP based solution. >VLC does not, and cannot modify the OUTPUT volume to destroy the speakers. That would be remarkable. >And as VLC is pres…

Dell may be using poor quality parts. VLC can also make the sound louder than any other media player that I've used while generating destructive square clipping.

The problem is it's too easy to set the volume above 100%. I've done so with the mouse wheel. And I now have a $2000 out-of-warranty laptop with blown speakers.

Fixes could include:

* Not remember settings above 100% between sessions unless an advanced option is checked that warns the user.

* Require a double click on volume slider to go above 100%.

VLC's high volume is a wonderful feature when you're listening to DTS or AAC movies encoded with the volume too low. It's just too easy to be accidentally abused.

Re: Installing VLC Media Player voids your speaker warranty

#105

Post by SixSigma »

guard-of-terra wrote: post #76
TeMPOraL wrote: post #73

Earlier quoted context omitted.

> I'm no expert but maybe it's actually possible to create speaker that doesn't go bad. Of course it is, but nobody wants to do that; it's not profitable. * sigh * . I sometimes wonder how difficult would it be to create, say, a brand of kettles with lifetime warranty, designed to last 50+ years instead of 50+ weeks the ones we have do. How hard would it be to sell them and to what ends would the competition go to st…

I never had either failing speaker or failing* kettle in my life so it's hard for me to say anything. Maybe there just so much you can get from laptop speakers so it makes sense to cap their power hard? * Some no loger turn off automatically, tho

> * Some no loger turn off automatically, tho

And you don't think a kettle burning its way through your kitchen is a fail !

Re: Installing VLC Media Player voids your speaker warranty

#106

Post by marcosdumay »

slacka wrote: post #104
fnordfnordfnord wrote: post #28

Earlier quoted context omitted.

Low quality speakers and a poor hardware design. It isn't even a challenge to match amplifier output to speakers in such a way that the amplifier can't break the speaker. There are easily a dozen cheap ways to make this work properly that don't rely upon a probably non-existent WMP based solution. >VLC does not, and cannot modify the OUTPUT volume to destroy the speakers. That would be remarkable. >And as VLC is pres…

Dell may be using poor quality parts. VLC can also make the sound louder than any other media player that I've used while generating destructive square clipping. The problem is it's too easy to set the volume above 100%. I've done so with the mouse wheel. And I now have a $2000 out-of-warranty laptop with blown speakers. Fixes could include: * Not remember settings above 100% between sessions unless an advanced optio…

The problem is, repeating the article and the GP, that it can not be abused.

Your computer was defective, and Dell is refusing to comply with the warranty. It's impossible for VLC to harm the speakers on a computer that is not defective.

Ok, I like it being hard to set volume bigger than 100% at mplayer, it'll probably be a nice feature at VLC. But that's only because I don't like clipping, not because of any hardware issue.

Re: Installing VLC Media Player voids your speaker warranty

#107

Post by gamache »

fnordfnordfnord wrote: post #86
astral303 wrote: post #74

Earlier quoted context omitted.

A square wave has twice the power of a sine wave of identical amplitude. This is why distorting the amplifiers (especially digital clipping) is so much worse for speakers than overpowering the speakers. This is a very well known fact in audio circles. Playing metal at full volume is not as damaging as playing anything intensely digitally clipped at full volume. Yes, Dell is putting on shitty speakers on their laptops…

>A square wave has twice the power of a sine wave of identical amplitude. 1.41 x >Playing metal at full volume is not as damaging as playing anything intensely digitally clipped at full volume. The output of the amplifier really ought to be bandwidth limited either as a natural consequence of the components used or explicitly with a filter. It is silly to spend power on things that can't be heard.

Assuming the parent is talking about equal maximum amplitude of the sine and square waves, the square wave RMS voltage will be sqrt(2), or 1.4, times the sine wave RMS voltage. And since power is proportional to voltage squared, the square wave will carry sqrt(2)^2, or 2, times the sine wave power.

Re: Installing VLC Media Player voids your speaker warranty

#108

Post by marcosdumay »

lutusp wrote: post #60
DrJokepu wrote: post #40

Earlier quoted context omitted.

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.

An entire category that I just tough as empty, before reading this article and discovering one element.

Have you heard about this problem in any other laptop before?

Re: Installing VLC Media Player voids your speaker warranty

#109

Post by im3w1l »

dzhiurgis wrote: post #59
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" :)

Void your dell speaker warranty with this weird deprecated firefox-only javascript http://ge.tt/7Qln5fJ1/v/0

Porting it to Web Audio API is left as an exercise for the reader.

Re: Installing VLC Media Player voids your speaker warranty

#110

Post by orig »

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…

"As the main developer of VLC". Sorry, but no: Rémi Denis-Courmont has contributed 2x more than you did.
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