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

211–220 of 224 posts

Re: Installing VLC Media Player voids your speaker warranty

#211

Post by userbinator »

ferongr wrote: post #190
jjoonathan wrote: post #170

Earlier quoted context omitted.

> VLC is to my knowledge the only average user-oriented program that can end up in such situations Windows Media Player, Firefox, iTunes, ... VLC makes it easier (you can boost a quiet song or movie until it fills the OS-defined dynamic range) but a loud song in any other piece of music playing software would have the same effect. Depending on the genres of music you listen to, it's not uncommon to come across songs…

>Windows Media Player, Firefox, iTunes, ... None of these drive the signal to digital clipping.

Yes they can if you play the right "music".

Re: Installing VLC Media Player voids your speaker warranty

#212

Post by PhantomGremlin »

laumars wrote: post #195
PhantomGremlin wrote: post #178

Earlier quoted context omitted.

Over on this side of the pond we generally use "coffee makers" instead of "kettles". But the problem is the same. They fail after a few years. It's all cheap consumer crap made in China. We've given up trying to buy "good" coffee makers. We just buy something cheap that's on sale and throw it away when it breaks. There should be the equivalent of "Gresham's Law" for consumer goods (the bad eliminates the good). But I…

We have coffee makers as well, but you can't make a cup of tea with a coffee machine. Nor make a cup-a-soup, pot/instant noodles, pre-boil water for cooking veg, hot water bottle, etc.

I used to boil water in a stovetop kettle. But that takes too long. So now I just use the microwave. Take a teabag, pour cold water over it, nuke for 90 seconds, DONE!

Of course it doesn't taste nearly as good as pouring hot water from a kettle onto a teabag, but it's so fast and convenient.

And I don't think anyone in the USA buys loose tea. It's all teabags here (i.e. probably 99% of the market).

Re: Installing VLC Media Player voids your speaker warranty

#213

Post by laumars »

PhantomGremlin wrote: post #212
laumars wrote: post #195

Earlier quoted context omitted.

We have coffee makers as well, but you can't make a cup of tea with a coffee machine. Nor make a cup-a-soup, pot/instant noodles, pre-boil water for cooking veg, hot water bottle, etc.

I used to boil water in a stovetop kettle. But that takes too long. So now I just use the microwave. Take a teabag, pour cold water over it, nuke for 90 seconds, DONE! Of course it doesn't taste nearly as good as pouring hot water from a kettle onto a teabag, but it's so fast and convenient. And I don't think anyone in the USA buys loose tea. It's all teabags here (i.e. probably 99% of the market).

The microwave trick not only tastes bad, but it also doesn't heat evenly as you get patches of boiling water and patches of cold water.

Modern kettles boil in about 2 minutes anyway. So I don't really see them as any more inconvenient than using the microwave. The real inconvenience is having to get up to switch the device on; what I really want is a networked kettle so I can boil it from the comfort of my seat hehe

Re: Installing VLC Media Player voids your speaker warranty

#214

Post by tmoertel »

lutusp wrote: post #206
tmoertel wrote: post #203

Earlier quoted context omitted.

OK. I think I see where our signals are getting crossed. I look at your diagram and think, The green signal g is not what you get when you try to output the red signal r but the output stage clips it at the supply voltage (my V ). Rather, the green signal g is what you get when you take the red signal r , amplify it by A = Infinity, and then try to output that new signal rA , which the output stage then clips. For al…

> It's just that I wouldn't call turning up the volume knob to be part of the "clipping" process, but rather amplifying. But it is, indeed it's the most common example of clipping in engineering practice. Consider two alternatives -- one in which the amplifier is able to accommodate a great increase in volume without any distortion, and another in which it cannot. In this image: http://i.imgur.com/g8txTmC.png The blu…

I agree with everything you wrote. Again, however, I think we're talking past one another. When you talk about clipping, you seem to mean turning up the volume until a signal clips. This both amplifies the signal and clips off its extremes. What I mean by clipping is to take a signal and clip off its extremes.

That sole difference explains our entire conversation. In your view, clipping involves making the signal bigger. That bigger signals carry more energy naturally leads to your claim. In my view, clipping a signal makes it smaller, leading to the opposite claim.

Thanks for sticking with me through the conversation.

Re: Installing VLC Media Player voids your speaker warranty

#215

Post by mikeash »

lutusp wrote: post #205
mikeash wrote: post #189

Earlier quoted context omitted.

In my opinion, it should be impossible to physically damage a computer from user-space code. I'm surprised that this seems to be such a controversial opinion. Given that, a computer which allows random audio API clients to destroy the computer's speakers is not correctly designed. Certainly, it may add cost, size, and weight, but if that's what you need for correctness, then that's what you need for correctness. The…

> In my opinion, it should be impossible to physically damage a computer from user-space code. I'm surprised that this seems to be such a controversial opinion. I don't find that controversial at all, but as time passes, it seems there are more ways that user activities can bring a computer down. The most obvious way is by sending out-of-bounds signals to storage devices that can erase or even physically damage them,…

In what scenario can userland code send signals that will physically damage storage devices?

Re: Installing VLC Media Player voids your speaker warranty

#216

Post by dpe82 »

gamache wrote: post #107
fnordfnordfnord wrote: post #86

Earlier quoted context omitted.

>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.

It also assumes a speaker's reactance is purely resistive. It's not.

Re: Installing VLC Media Player voids your speaker warranty

#217

Post by weland »

etjossem wrote: post #123
weland wrote: post #100

Earlier quoted context omitted.

Cheap shit. Seriously, cheap shit. There are several ways to solve this, all of which boil down to "use more chips" or "use better speakers", thus increasing the price of already incredibly shitty speakers. Source: I'm involved in designing consumer electronic products and the only corners that don't get cut are those that, if cut, result in certifications not being granted and therefore in products you're unable to…

This is great information - and I'd love to know which speaker manufacturers you approve of. I'd rather own an expensive set of desktop speakers that lasts ten years than deal with Dell parts breaking all the time.

> I'd love to know which speaker manufacturers you approve of

I have no idea how things go in the laptop market, so I can't say there's one I approve of in particular. The fact that the ones on the laptops are crap can, however, be assessed quite easily by ear :).

Re: Installing VLC Media Player voids your speaker warranty

#218

Post by fxsoap »

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…

Dell can't agree with this without having to do a hardware recall or refund people. It is much easier to blame your software (and cheaper by a hundred million of dollars in bad press/computer returns/hardware thrown away/call centers dedicated to this issue/etc etc).

Sad to see behavior like this

Re: Installing VLC Media Player voids your speaker warranty

#219

Post by lutusp »

mikeash wrote: post #215
lutusp wrote: post #205

Earlier quoted context omitted.

> In my opinion, it should be impossible to physically damage a computer from user-space code. I'm surprised that this seems to be such a controversial opinion. I don't find that controversial at all, but as time passes, it seems there are more ways that user activities can bring a computer down. The most obvious way is by sending out-of-bounds signals to storage devices that can erase or even physically damage them,…

In what scenario can userland code send signals that will physically damage storage devices?

Over my long career (approaching 40 years) I've seen any number of peripheral devices that responded to bad instructions by tearing themselves to pieces. One example would be a HDD driver that inadvertently ordered the R/W heads to move to a nonexistent location. That's pretty common, and sometimes results from a bug in the code, not anyone's intention.

Another common error is to allow a system power shutdown without parking the HDD R/W heads in a sacrificial area, so subsequent mechanical shocks won't cause the heads to collide with a legitimate data surface. This problem can be caused by insufficient power supply capacity -- a capacity that must detect the power shutdown and allow the head traversal to complete before the remaining power is used up.

Just examples, there are many similar ones.

Re: Installing VLC Media Player voids your speaker warranty

#220

Post by userbinator »

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…

DC protection = a IMHO everyone who is saying "this should be fixed by software" is doing it wrong. How much would it cost to write, test, debug, etc. the appropriate firmware/drivers? And it would still be subject to "warranty is void because you didn't use the right software". That cost could buy a lot of capacitors... and then if the values were chosen correctly, whatever the software does, it would not be able to put more power through the speaker than designed.
Post reply on HN