Sneaking Past Heavy-Handed Audio Compression on YouTube

niceone writes "Recently YouTube seems to have started applying extreme compression to the audio of uploaded clips. This is the type of compressions used by radio stations to make everything louder, but in this case applied extremely badly. In quiet passages, breathing and shuffling become overpoweringly loud. A gently plucked guitar chord becomes a distorted thud. Listen to an example here. And here's what it could sound like — still not perfect, but a whole lot better. The fixed version is thanks to a workaround proposed by Sopranoguitar — the idea is to turn down the audio and mix in a high frequency sine wave (I used 19kHz). The sine wave fools YouTube's compressor into thinking that the file is at a uniform level (and does not need the volume changing at all) but is filtered out by the encoding process (so, no need to worry about deafening any dogs)."

Comments

This hurts

[Compuser]

Can someone post an example I could possibly listen to for more than one second?

Re:This hurts

[_xeno_]

Sure, how about the given example? One second is really all you need.

In the heavily compressed one, you hear an annoying hiss and the sound of the microphone being moved for the first few seconds.

In the non-heavily compressed one, you don't.

That's really the complete example without having to listen to the song. Really, the first few seconds are the best example, because Google is apparently amplifying almost complete silence to noise. The song part really doesn't help much. (Or at least, as much as I was willing to listen to it, which was only a few seconds.)

Re:This hurts

[drspliff]

The worst examples I've seen have been videos of a lecture/speech, and while the main speaker has a microphone it also picks up sound from around the auditorium or lecture hall.

Normally this is fine as we have all become accustomed to faint background noise, with this extreme compression the faintest cough or shuffling in the audience sounds is as loud as the person speaking and is thus very distracting.

Considering most of the lectures I view are 30+ minutes long this really pisses me off.

Re:This hurts

[niceone]

Heh, yeah, I did consider that, but you do only need to listen to the first bar to hear the problem.

Re:This hurts

[empaler]

http://www.youtube.com/watch?v=HiHMZG0Vg-s

Re:This hurts

[old and new again]

see my newest videos, uplaoded this week, as soon as I drop the kick the level jumps 6-10 dB and when the kicks come back it squashes and pumps like a benassi bassline (not in a good way) http://www.youtube.com/profile_videos?user=muzik4machines compare the newest one (destroyed by youtube) and some older ones where it sounds almost exactly like my original mix (at 22KHz, but still, not squashed) and t does so with the quick uploader as well as the uploaded videos, which is even worse, the quick uploader, i would understand as people uses built in mics and stuff, but my final, mastered HD performance is squashed all life out of it, mono-ified and downsampled to 22, 050 KHz, it's not really an incentive for artists to upload their stuff anymore, it makes you sound liek you don't know how to mix properly (and it does it with the qui

Re:This hurts

[old and new again]

http://www.youtube.com/profile_videos?user=muzik4machines listen to the 1st 5 clips for bad compression, listen to anything older and it is significantly better, even the quick capture ones

and who came up with it?

[X0563511]

Who's the mentally... challenged... individual who decided that applying such compression in the first place was a good idea, and then proceeded to implement or accept such a shitty implementation?

Re:and who came up with it?

[saxoholic]

Well, it starts with the "Loudness War" Record companies/radio stations compete to make everything louder, because the louder the music is coming over the air, the more likely the listener is to notice it. I don't see how that would help youtube though, because we're not listening to youtube in the background like we are to the radio.

Re:and who came up with it?

[larry bagina]

youtube is a huge money sink. They probably can't afford to hire people that have experience in audio compression, test different algorithms, etc. As to why... video and sound quality varies a lot, so they probably are trying to make everything more equal, so the viewer doesn't need to adjust their volume for every video.

Re:and who came up with it?

[Tablizer]

I have to admit that I don't like it when some videos are blaring loud and others so quiet[1]. I have to keep jacking the knob up and down. However, perhaps rather than alter the original sound, they could have the volume knob (optionally) adjust to the appropriate volume for a given video.

[1] Is the youtube-side volume adjustment new? Many existing vids seem to be all over the place volume-wise.

Re:and who came up with it?

[Anonymous Coward]

I have to keep jacking the knob up and down.

To YouTube videos? Sicko!

Re:and who came up with it?

[mdmkolbe]

I don't think YouTube is trying to run a loudness war, but rather trying to fix up a lot of amateurish recordings that are uploaded with bad audio. I can't tell you how many recordings on the net are either way to quiet (e.g. I can't hear speech even at max volume) or too loud and that change in mid-video (e.g. person walks away from or closer to mic). Despite their good intentions, though, it seems to have fallen prey to the "Clippy" effect.

What YouTube needs to do is have a little check-box on uploads that indicates whether to apply the auto-balance. And in case an uploader asks for no auto-balance when they really shouldn't (e.g. they think they know but don't) there should be a side link to listen to the auto-balanced version.

Re:and who came up with it?

[MightyYar]

To YouTube videos? Sicko!

What can I say? Unrehearsed rants into webcams really turn me on...

Re:and who came up with it?

[daem0n1x]

I guess they are trying to compensate for the huge differences between recording quality in the videos people submit. Some are loud enough, others are very low and you have to turn the level way up to understand what people are saying.
They could simply normalise the level, but if you have a speech with very low level and the guy drops the microphone in the middle, that one peak is so loud that will make the normalisation process useless.
But compression is such a complex and subjective issue that it should be performed by hand. I guess they have an automated process for that, and it doesn't have any intelligence, just steamrolls all the audio it finds, whether it's speech, music, or anything else.

Re:and who came up with it?

[PopeRatzo]

All they'd have to do is, as mdmkolbe says above, is put some checkboxes up for the uploaders, to choose from a few default compression algorithms, or a box to check if you just want them to leave your audio alone.

Was there really a big problem with inaudible YouTube videos before this, though? Is this a solution that really didn't have a problem?

Re:and who came up with it?

[daem0n1x]

they could have the volume knob (optionally) adjust to the appropriate volume for a given video.

They do, it's called compression.

Re:and who came up with it?

[Tablizer]

I meant without altering the encoded sound level in the *file*. In other words, client-side adjustment, but also client-side alterable.

Re:and who came up with it?

[billcopc]

Louder is one thing, compression is another.

Compression can help bring out the faint natural harmonics in a sound, making it "warmer", not unlike an overdriven tube amp. These harmonics are like ear candy to most people, subliminally making the sound more enjoyable.

Radio stations do it for various reasons, one is it helps them sustain peak output power. Another is that the average radio is a cheap chinese gadget that sounds like liquid ass, so the compression actually helps with the sound quality on those devices. When you also consider where radio is often heard, e.g. malls, outdoor venues, cube offices, you realize these are all substandard listening environments where high dynamic range really means you lose half the sound, so the compression again helps with perceived quality by driving most of the content above the noise threshold.

There are plenty of good reasons for sound compression, but its use should be toggled by the user, and for the love of god, give it some sane thresholds! For most content, anything above 4x compression is overkill!

Re:and who came up with it?

[X0563511]

They need to allow a means of bypassing the compression, then.

Re:and who came up with it?

[billcopc]

But what if you move away from the mic to breathe ?

Chocolate Rain
*whoooosh*
Youtube makes my breathing loud again
Chocolate Rain
*whoooosh*
My eardrums are whimpering in pain

Re:and who came up with it?

[anotherone]

The typical youtube uploader can't even manage to tag their videos properly. Giving them MORE options is just dangerous.

Re:and who came up with it?

[archeopterix]

This is just in. Studies have shown that on a popular site named Slashdot LOUD COMMENTS ARE MODERATED BETTER THAN QUIET ONES!!!

Re:and who came up with it?

[Yvan256]

Leave Chocolate Rain alone! Leave him alooone!

Re:and who came up with it?

[eh2o]

Compression can help bring out the faint natural harmonics in a sound

Only a multiband compressor can do this, otherwise it just raises the level of all harmonics by the same amount.

If the one on YT is fooled by a 19khz sinewave then its single band compressor.

3:1 compression is usually considered the upper limit for practical purposes. Most people do prefer a small amount of compression.

Re:and who came up with it?

[Anonymous Coward]

Oh god do I miss 4chan..

Re:and who came up with it?

[Anonymous Coward]

WPLJ 95.5 in NYC knew this very well back in the 70's they' use massive audio compression to keep the modulation index of the carrier at 95.5%... That needle just say there!

My station WDJF 107.9 Westport CT cared about audio quality. The MI followed the full amplitude of the source audio. Fed by 2 channels of full 15 khz equalized ma-bell-telco pairs. We sounded good! But PLJ was much much louder.

Re:and who came up with it?

[danwat1234]

It puts the Acidic Melted Chocolate on its skin again!

Re:and who came up with it?

[hairyfeet]

Are they making money with it? The first time I saw Youtube I thought "Yeah,the users will like it. But make money with it? It'll be pets.com all over again." If they use the traditional text ads they won't work as nobody will notice them,and putting ads before allowing the vid to play will just p*ss off the users and cause them to run away in droves. I know when I click on a weblink for a clip and some commercial starts playing I instantly close the tab. TV ads have gotten so bad I almost never watch anymore,and I sure as hell ain't going to watch a 30 second commercial for the privilege of watching a minute and a half clip.

So i would love to see the numbers to see how much money they are spending on Youtube VS how much is coming in,because I'm betting it is a giant black hole of money suckage. But as always this is my 02c,YMMV

Re:and who came up with it?

[Tacvek]

But cant they do simple volume equalization rather than compression? I mean equalizing by either maximum volume (the loudest sounds in all videos are exactly the same) or by the average volume (the avaerage volume level of all clips are exactly the same).

Indeed, I believe they already do use one of those equalizations. So why compress the sounds?

Re:and who came up with it?

[X0563511]

Then hide the options. You don't protect the idiot by rubber-coating all the corners in the room, you protect them by putting the knives out of reach.

Re:and who came up with it?

[olyar]

You're not the only one wondering. Investors are as well. Found this story called Youtube Ads Underperforming

Re:and who came up with it?

[old and new again]

compression is ok, its 20 dB of automatic make-up gain that is not human (and upward expansion to bring the low levels at the average RMS(which is even more painfull to my engineers ears)

Re:and who came up with it?

[perlchild]

for [1] The useful article summary just said "they started implementing it". So yes it's new, say a few weeks ago at most.

Re:and who came up with it?

[Anonymous Coward]

the same thing but just increased in volume

We are not talking about an increase in volume, here, but an increase in loudness (ie. a flattening of the dynamic range).

Re:and who came up with it?

[hairyfeet]

Thanks for the info. i also found this by following links connected to your link,which talks about Google rolling out new ads which will take up the bottom 20% of the ENTIRE video clip. While I am sure that they will still get uploaders trying to cash in, I'm betting that to try to stop the bleeding they will end up with ads running pre roll,post roll,and with this overlay running the entire time. Which of course will run users off in droves,as nobody wants to sit through 30 second commercials just for a 1-5 minute clip. And then adding a stupid commercial sucking up the bottom 20% of the entire video is going to be distracting as hell,as they'll HAVE to make them flashy so your eyes will look down at the stupid thing.,

Which of course illustrates the problem with trying to support a video site through ads. because the folks are busy watching the video you're going to have to make the ads flashy and annoying just so you can drag folks eyes away from the video long enough to pay attention to your ads. Or you have to do like MSNBC and run the damned things before the content which I'm sure ends up with a lot of folks doing like I do and just killing the tab rather than watch the stupid ad. I would love to see the data from sites that run the ad before you can see the content just to see how many kill the site before actually getting to the content. I know watching my boys surf they do the same thing. If they have to see a 30 second ad just to see the clip they just don't bother.

The only video sites where I can see the ad model really working out would be the porn sites like Redtube. Since folks will keep watching the ads thanks to the sex in them,and they can tie the ads easily to the vids. Something like "Hey,you like that lesbian clip? We have the Debbie does the cheerleading squad on sale this week!". They can tie in with videos,toys,etc and I bet their click through rate is a whole lot better than anybody else. But considering the bandwidth required for something like Youtube,along with the server space,I just don't see how they will keep from irritating the hell out of users and still have the ads generate enough capital to pay the site's expenses. But as always this is my 02c,YMMV

Re:and who came up with it?

[MadKeithV]

Technically compressors don't raise the level either, they reduce it. It's the make-up gain afterward that raises the level.

Re:and who came up with it?

[Keeper Of Keys]

I can't tell you how many recordings on the net are either way to quiet (e.g. I can't hear speech even at max volume) or too loud and that change in mid-video (e.g. person walks away from or closer to mic).

You can tell me, I'm a doctor.

Re:and who came up with it?

[MadKeithV]

That's STILL compression :)

Re:and who came up with it?

[MadKeithV]

If that's really what they wanted to do then they should have stuck with much milder compression and audio normalization.
Therefore I think YouTube *is* trying to run a loudness war.

Re:and who came up with it?

[Prune]

That's why I rarely listen to modern recordings. Unless you buy from the few brands that specifically avoid this, you end up with something with a dynamic range that makes a turntable seem good (ironic, considering increased dynamic range is the CD's big sound-quality-related benefit over records).

Re:and who came up with it?

[MadKeithV]

They don't have to be flashy at all - I think it could work. If non-flashy text ads works for google search, why couldn't subtitle-like adverts work for YouTube?

Re:and who came up with it?

[Gage With Union]

Compression can help bring out the faint natural harmonics in a sound
Only a multiband compressor can do this, otherwise it just raises the level of all harmonics by the same amount.

If you want to boost the harmonics, improve intelligibility and make it sound richer, an Aural Exciter might be what you want. Though it might help, multi-band compression is not really intended for this. Also, as per the OP, single-band compressors are generally designed to limit the production of modulation artifacts. It's designed to boost levels, which may bring out faint harmonics, but will more likely, in the case of people's YouTube videos, boost background noise.

Of course, if I had it my way, I'd just put a flanger on everything.

Re:and who came up with it?

[The Gaytriot]

* I set my sine wave to 19khz to breathe

Re:and who came up with it?

[Anonymous Coward]

Audio discussions need a sort of "Godwin Equivalent" that I can drop every time someone steers a completely unrelated audio conversation in the direction of "loudness war" complaints. It's nearly as trite.

Re:and who came up with it?

[hairyfeet]

Because the have done studies using special glasses that track eye movement so to find out where

the best place to place products in ads is. That is why for things like sunscreen they and body sprays they put the product close to the hot babes breast or face. Because studies shows that the eyes naturally head for those two areas. So the only way an ad inside a video is going to work is to either place the where the studies have shown the users eyes are going to travel,or make them so flashy that the eye will naturally look down to see what is going on.

I have seen studies based on eye movement on web pages,and the same theory holds. If your ads is in the top left 35% of the screen you will get seen a lot more than being in the middle or right side. Folks just don't realize that their eyes naturally go to certain quadrants when doing anything involving watching or reading. But I bet Google has seen those studies and knows that a non flashy text ad simply won't be seen because the human eye will not look down nearly as often because it is in the wrong quadrant. But as always this is my 02c based on what I've read,YMMV

Re:and who came up with it?

[X0563511]

It all depends whom your modern recordings come from. Myself, I've made a few (and you don't want to hear them, they are quite amateurish crap really) and I don't compress. I simply amplify the whole thing so that the highest peak is at 0dB.

However, this only works fine when you have a nice quiet environment, and good quality listening equipment. A typical place to listen to music, such as in a car, needs the compression, as all the external noise drowns out anything below a given floor.

There's no real quick-fix, no one-shot solution. You either release compressed media along with uncompressed, or you give the uncompressed media and let the end-user compress it as required. This can be done in the playback hardware/software quite easily.

Re:and who came up with it?

[Prune]

I'm one of those silly people that builds their own equipment ^_^

The quiet environment is actually not as necessary as you imagine, since one nice way to listen is by using in-ear-canal headphones, such as Etymotic ones. They provide something like 30 dB isolation from outside sound in mid and high frequencies. Combine this with the fact that the ear can pick out a signal several dB below the noisefloor (because noise is broadband whereas signal generally isn't), and one can begin to see that 24-bit audio may make sense (noise-shaped dithered 16-bit can only manage the ear's 120 dB range in a narrow part of the frequency range). Of course, it's hard to make electronics reach such low distortion, and drivers, be they headphones or speakers, have even higher distortion (though it tends to be predominantly linear distortion, unlike the electronics where the problem is the exponential gain of transistors or the 3/2 power law gain of tubes).

Re:and who came up with it?

[WNight]

What do we want Youtube for though? It should be replaced by light-weight torrents and a good search page. In fact, you could seed it with everything on Youtube, including - if you really hate the world - the comments.

Wouldn't it be easier

[phantomfive]

Wouldn't it be easier to set your gate correctly? Cut out the background sounds BEFORE submitting to youtube; do proper editing and then it doesn't matter so much what they do. Here, in my opinion, is a good site for all such information.

Re:Wouldn't it be easier

[PetiePooo]

Wouldn't it be easier to set your gate correctly?

That would apparently help, but only in cutting out the quiet scrapes and shuffles before the actual (attempt at) music starts. During that silent period, YouTube's encoder would be cranking up the gain so much that, when the first guitar pluck occured, it would still be a highly clipped thud. This workaround keeps them from adjusting the gain at all.

In other words, prefiltering your audio stream with a gate would quiet down the quiet parts, but would not prevent YouTube's encoder from fiddling with the gain.

Re:Wouldn't it be easier

[4D6963]

During that silent period, YouTube's encoder would be cranking up the gain so much that, when the first guitar pluck occured, it would still be a highly clipped thud.

Well actually it really depends. It depends whether it's audio compression, or volume normalisation. If it's audio compression then things get amplified regardless of chronology, and therefore if you remove the ambient noise it won't get amplified to an audible hiss and it won't have a negative effect on anything else.

However what you were thinking about is "volume normalisation". In that case a quick change if volume would have the effect you described. I'm not sure which it is in this case but from the summary it looks like it's audio compression.

By the way, noise gating? There are more sophisticated things these days for that, like stuff based on STFTs and noise profiling.

Re:Wouldn't it be easier

[Ethanol-fueled]

But a noise gate's pumping and breathing may only aggrivate a compressor's worst attributes(which, coincidentally, just happen to be "pumping" and "breathing" since a comp is a dynamic effect like a noise gate).

Since many of the "you"-style(as in YOUtube) recordings like home-video style recorded lectures, performances, etc. are used with a mic, then the noise gate(especially in conjunction with a comp) will only amplify the imperfections.

In other words: slownewsday, stop whining. If it's that much of a hassle then rip the audio and master it yourself.

Re:Wouldn't it be easier

[Max Night]

Yeah but if you're posting something musical - this doesn't apply at all. It's not a matter of cutting out background noise, it's about screwing up the mix. :)

Re:Wouldn't it be easier

[Anonymous Coward]

It still matters what they do. This kind of high compression is unsuitable for most material, yet they're insisting on it. Not only does it completely kill the dynamic range - imagine going to see a classical music concert and the entire concert is played at the exact same volume, no crescendos or decrescendos - that lack of dynamic range also dramatically quickens ear fatigue. What they're doing is great if they want people to stop listening (and therefore likely watching) YouTube videos as much. Otherwise, it's a really dumb idea.

Using a noise gate to solve YouTube's poor decision is not very realistic - that's trying to get thousands and thousands of different people to fix something caused by YouTube trying to solve what wasn't really much of a problem. What's more, noise gate + high compression leads to Charlie Brown Special kinds of voice tracks and very limited musical choices - e.g., in a classical concert, instead of the quiet parts being just as loud as the loud parts, some of the quiet parts will simply be cut to silence. Noise gate + high compression can be cute for a bit in dialogue, and when done to a particular instrument - but not every instrument in a song - you can get some cool effects from it, but it's shitty thing for YouTube to require of people. It may be enough to force some users away.

Re:Wouldn't it be easier

[zalas]

It depends on the parameters of the compressor used. If the compressor has a long attack time and no look-ahead, you'll get that the compressor doesn't have enough time to clamp down a sudden loud burst of sound.

Re:Wouldn't it be easier

[Anonymous Coward]

No, it's the other way round. He is really is thinking of compression.

Normalising has no effect on the sound, other than an overall gain change. It's an offline process done by analyzing the entire length of the audio.

Compression is dynamic and constantly changing. It's done by doing an rms or peak average of a moving window of few milliseconds of audio.
The 'highly clipped thud' artifact petiepoo mentioned happens because of this short analysis window. The time constants of the compressor cannot respond fast enough after the gate opens and you get a thump.

As normalisation does not require calculating rms or have time constants, it does not create the same artifacts.

Re:Wouldn't it be easier

[4D6963]

Normalising has no effect on the sound, other than an overall gain change.

It's not what I'm talking about. I'm talking about "volume normalization" as VLC calls it, which matches to the description I gave of it.

Also the "compression" you're talking about is the "volume normalization" I was talking about. I thought that compression was simply accomplished by directly applying a function to the sample values?

Re:Wouldn't it be easier

[Teetow]

I think we're confusing the terms here. I'm not sure what you mean by audio compression, but if it's dynamic compression you're talking about (which is what is heard in the example) then chronology definitely plays a part. What Google seems to be doing is to make sure the volume stays fairly consistent between clips, which is a noble enough goal. The problem seems to be that they've applied a very ham-fisted algorithm (translated to compressor terms, their ratio, threshold, release and makeup gain settings are too aggressive) but I suppose this is what they considered necessary given the extreme range of material posted on YouTube on a daily basis. I applaud the effort, but the end result could have been a lot better.

Re:Wouldn't it be easier

[Anonymous Coward]

Ah, it appears we have some crossed wires.

I was using the terms 'normalization' and 'compression' in the manner they are used in the audio production industry. I assumed you were doing the same.

Doing a quick google for 'volume normalization', it appears that term is used interchangeably for both normalizing to peak, and for what I would call compression. It seems to be a term mostly used in mp3 encoding software.

Nomalizing and compression are actually distinct processes. At least in my understanding. A compressor is something like an 1176 with attack and decay times, and normalization is an offline process in a digital editor, where the only variable is the highest sample value.

Re:Wouldn't it be easier

[blincoln]

It's not what I'm talking about. I'm talking about "volume normalization" as VLC calls it, which matches to the description I gave of it.

Normalization applies the same change in amplitude to the entire input.

Compression is different. It's being used in this discussion in the audio processing sense, not the "making a file smaller" sense. It (basically) varies the amount of amplification based on a sliding window. It's typically used to reduce the amount of difference between the highest and lowest amplitude parts of a sound (or song, etc).

Maybe an example will help. If you take a sine wave and normalize it, it will still be a sine wave (just with higher peaks and deeper valleys). Compressing it instead would "squash" it vertically, so it would no longer be a true sine wave. This is a bit simplified - at least in my experience a compressor is typically set for time scales much greater than a single cycle of a sine wave, e.g. to "squash" drum sounds down to more consistent levels.

What YouTube is doing as described in TFA is compression, not normalization.

Re:Wouldn't it be easier

[PetiePooo]

Well actually it really depends. It depends whether it's audio compression, or volume normalisation.

From listening to the sample, it sounds like volume normalization to me. When the video clip starts, it starts fairly quiet, but soon you start hearing shuffles and scraps as the codec apparely ramps up the gain.

The guitar pick turns into a thud for the first few milliseconds, but then the actual tone comes out for a moment as the codec apparently turns down the gain. However, it quickly starts turning it back up again, as the next pick again sounds like a thud.

Besides, if it were audio compression, the guitar picks wouldn't be clipped and distorted so badly; they just wouldn't be so loud. Plus, you'll notice the scrapes and shuffles disappear once the "music" starts. Wouldn't compression try to make those softer sounds louder even when there are loud passages immediately surrounding them?

Further experiments could verify this, but its my understanding that they're just applying AGC in a very aggressive fashion. From 10kft view, that makes sense, as teens submitting cellphone clips aren't normally going to ensure their audio levels are normalized.

Re:Wouldn't it be easier

[Theaetetus]

If it's audio compression then things get amplified regardless of chronology, and therefore if you remove the ambient noise it won't get amplified to an audible hiss and it won't have a negative effect on anything else.

Except that quiet passages will be amplified, reducing the overall dynamic range. Consider something with a wide range of volume, like Ravel's Bolero. Under compression, the soft passages at the start - not merely ambient noise, but the first 5 minutes - will be heavily amplified, with the amount of gain decreasing as more instruments are added in. Instead of a gradual build from very soft to very loud, you would instead get a very slight build from loud to very loud.

However what you were thinking about is "volume normalisation". In that case a quick change if volume would have the effect you described.

And here, it wouldn't... Normalization (or with an s if you're British) scans the entire piece of audio to find the loudest possible peak, and it then adds a set amount of gain to the entire track to bring that peak up to your desired level.
For example, say your same Bolero goes from -48 dB FS during those soft passages to -6 dB FS at its loudest peak at the very end. Normalization would add 6 (or most likely 5.9) dB to the entire song, so it would still have the exact same dynamic level: 32 dB, going now from -42 to -.1 dB FS.

Thing is, normalization normally won't cause clipping, because it's setting the loudest impulse to just below the clip point. Horribly applied normalization may, however, but that's besides the point.
On the other hand, it's very easy for audio compression to cause clipping, simply by setting the makeup gain poorly.

Update

[niceone]

After some more testing it seems that there is a problem with high quality mode. With the tone and sample rate I used (19kHz and 44.1k) at least the high quality encoder whistles at, some other frequency. Sounds like somewhere less than 10kHz to me.

I hope YouTube fix this soon.

Re:Update

[4D6963]

Any chance this would be due to a non-linearity like clipping? Someone correct me if I'm wrong but I think that with clipping with a strong 19 kHz component in a signal sampled at 44.1 kHz you'd get artifacts which base frequency would be 3,050 Hz.

Re:Update

[Anonymous Coward]

It looks to me like Google have done this on purpose to stop people uploading high quality audio with a still image. A lot of the music I've been listening too recently has been from youtube, I'm sure I'm not the only one...

Re:Update

[pz]

AWith the tone and sample rate I used (19kHz and 44.1k) at least the high quality encoder whistles at, some other frequency. Sounds like somewhere less than 10kHz to me.

Like, say, 3.05 kHz? That's what one would expect from a non-linear mixing of the sampling frequency and the signal you've injected. There are so many potential sources for non-linear mixing that it's hard to start a meaningful list, but here goes: gain control, compression, resampling, clipping, aliasing, unintentional digital-to-analog-to-digital conversions, non-idealities in the audio driver amplifier, etc. The problem could originate at your end when you created the audio stream, at the far end when they normalized it, at the near end during playback, etc. And that's just off the top of my head.

But, non-linear mixing between the signal and sampling rate is probably the culprit.

Re:Update

[Anonymous Coward]

Clipping typically isn't a problem at 19KHz... it's more likely to be another type of modulation artifact (e.g. bad re-sampling algorithm or a broken lowpass filter). Intermodulation would definitely distort down there to ~3KHz, but IM is an analog artifact, not (except in very rare circumstances) digital.

Re:Update

[4D6963]

Huh?? Why on Earth shouldn't clipping be a problem at 19 kHz?

Re:Update

[Anonymous Coward]

Because 19 kHz is usually so low volume compared to the lower frequencies. I see what you mean, though -- due to the mixing property of PCM, _everything_ gets clipped when the volume goes too high.

Re:Update

[Anonymous Coward]

Can you please, please, for the love of god, learn the difference between "to" and "too" and when to use which. Here's a hint: which one you use does NOT depend on how you say it. Fucking moron.

Re:Update

[Anonymous Coward]

"sounds" like aliasing?

http://en.wikipedia.org/wiki/Aliasing

Quoting wikipedia: "Temporal aliasing is a major concern in the sampling of video and audio signals. Music, for instance, may contain high-frequency components that are inaudible to us. If we sample it with a frequency that is too low and reconstruct the music with a digital to analog converter, we may hear the low-frequency aliases of the undersampled high frequencies. Therefore, it is common practice to remove the high frequencies with a filter before the sampling is done."

I'm not 100% sure (maybe there are other factors) but it seems like the "High Quality" encoder is NOT sampling at 44.1 kHz but closer to 22 kHz hence the ghost frequency at around 10 kHz

Re:Update

[4D6963]

Did you even read TFS? We're talking about a 19 kHz sine louder than the rest of the sound.

Re:Update

[Distortions]

That is NOT audio compression, that is automatic gain control (AGC). Huge difference. Audio compression makes loud and soft sounds closer to the same volume. Automatic gain control changes the gain based on the current volume ( thats why the hack works! ). In the high quality video I can hear something from the tone he added, it wasn't completely filtered or some harmonic of the tone got through. Still, not a bad hack :)... I wonder if a sub-sonic tone would work. Not only is youtube using AGC, its badly set up AGC. It would be fine if they set the release time higher and kill the response time so it doesn't clip when the volume increases. Or, they could do something even better and use real compression or even a multi-band compressor. Multi-band would be great, it would make the tinny webcam mics sound a lot better by balancing the equalization a bit.

Re:Update

[mesocyclone]

You are probably hearing aliasing. If your 19kHz has harmonic content (which can be introduced several ways), it will mix with the 44.1Khz sampling frequency, producing sounds at the sum and difference frequencies (for example 44.1 - 38 = 6.1).

Re:Update

[Anonymous Coward]

Man, you really need to get laid. A little uptight huh?

Re:Update

[Hyperspite]

I'm a bit of a noob, but if you're clipping on a 44.1 kHz sampled signal, wouldn't the clip be at 22kHz? That's where the sampling theorem states you can't get any more nonaliased signal.

Re:Update

[jordan314]

I'm surprised no one has mentioned that youtube audio is still mono. I enjoy listening to music from youtube too, and there are plenty of free online tools to rip mp3s from the videos, but it drives me nuts that almost all of the videos are mono - this is a way bigger issue to me than the compression.

Re:Update

[4D6963]

Oh that's not the same clipping we're talking about. The clipping we're actually talking about is when sample values get hard-limited, which creates distortions (also referred to as non-linearities because they emerge from having the sound go through a non-linear system, in this case a function that forbids a sample value from exceeding a certain value) and can make even ultra-sounds produce audible distortions, which is one of the two main principles behind the so-called "sound laser".

Re:Update

[Anonymous Coward]

AGC and compression are the same thing.
Your definition: "Audio compression makes loud and soft sounds closer to the same volume. Automatic gain control changes the gain based on the current volume"
does not make any sense. You have just said the same thing twice.

Re:Update

[Anonymous Coward]

Not only is youtube using AGC, its badly set up AGC. It would be fine if they set the release time higher and kill the response time so it doesn't clip when the volume increases.

Yes, it could be improved upon, but no single set of parameters can ever be satisfactory for all of such an enormous range of material.

Because of that, and because some people do know what they are doing, it would be wise for them to make this optional, or at the very least offer RMS normalisation (adjustment of the overall volume based on a loudness average taken over the entire length of the video) as an alternative.

Or, they could do something even better and use real compression or even a multi-band compressor.

Multi-band would be great, it would make the tinny webcam mics sound a lot better by balancing the equalization a bit.

Multi-band AGC/compression can indeed be beneficial on some material, including cheaply-recorded speech, provided that it is set up appropriately for the material at hand - so again, they would have to provide different options for different kinds of material for it to be of any practical use.

Re:Update

[Pope]

Fine by me, the more they stamp out these stupid "videos" the better.

Re:Update

[Hyperspite]

ahhh. Thank you! That makes a lot of sense.

Re:Update

[Distortions]

Well, the distinction is compression does not check the current volume and then respond to it, it processes every sample the same way.

Re:Update

[Anonymous Coward]

No, I admit I haven't. :)

Clipping doesn't do much to a sine wave in the last octave - you can check this in an audio editor. The square wave harmonics are too high to be represented and get chopped off by the anti-aliasing filter.

Re:Update

[4D6963]

Clipping doesn't do much to a sine wave in the last octave

Spoken like someone who needs to get a clue. It has nothing to do with harmonics by the way, only with the difference between the non-clipped and the clipped signal.

Just sneak past the entire recompression process?

[4D6963]

Wouldn't another solution be to sneak past the entire recompression process by submitting a .flv video that meets YouTube's requirements to avoid recompression? Or would the compression on audio (not the same type of compression, the one this article is talking about) still be forced on these?

By the way to improve the trick, what you could do is detect the envelope of your sound, a modulate your 19 kHz sine with an envelope complementary so that the two envelopes would sum up to a flat line, so your 19 kHz envelope would be f(t) = 1 - original_sound_envelope(t).

Standards

[Dan East]

YouTube is just trying to enforce a standard level of quality to the content. Everyone expects crappy video with lots of compression artifacts, so the audio might as well follow suite.

Re:Standards

[Anonymous Coward]

that would be suit w/o the "e".

Compression

[retchdog]

I can understand why youtube does this (apart from the scream videos...) - a lot of people browse on laptops which have terrible audio. Thinkpads are especially awful; when I play video on VLC without headphones, I set the volume at 1600% and suffer the clipping - at least I can hear it over, say, a room A/C.

Is anyone aware of a lower-level playback compressor on Windows and/or Linux, perhaps a virtual device driver, which lets you mangle your sound this way? VLC doesn't work for everything after all.

Re:Compression

[AvitarX]

I don't know about the practicality, but I read a tutorial of running all of your sound (In Linux) through Jackd.

You could then run your applications through the jack rack and tweak it however you wanted.

Re:Compression

[4D6963]

Did you try VLC's "volume normalizer"? It's not compression but it makes more quiet passages louder. And if your ambient noise problem is that bad, it may damage your hearing in the long term depending on how loud it really is.

Re:Compression

[Mprx]

ALSA supports LADSPA plugins. Example compressor/limiter setup here: http://alsa.opensrc.org/index.php/Ladspa_(plugin) I use this for watching movies at night without disturbing neighbors, works very well.

Re:Compression

[retchdog]

I live in a metropolitan area so there's only so much I can do about ambient sound. But seriously, it doesn't take much more than quiet background conversation or a standard room A/C to drown out my laptop. Thanks for the tip, I'll look through the miasma of VLC's options again - I guess that it preprocesses the whole file instead of doing it on-the-fly? That'd be better.

Re:Compression

[retchdog]

It sounds a bit more heavyweight than I'd like, but I've been curious about the network streaming of jackd. Interesting, maybe I'll get off my duff and set it up. Thanks for the tip.

Re:Compression

[Liket]

Try Breakaway -

http://www.claessonedwards.com/

Re:Compression

[Stormwatch]

a lot of people browse on laptops which have terrible audio. Thinkpads are especially awful; when I play video on VLC without headphones, I set the volume at 1600% and suffer the clipping - at least I can hear it over, say, a room A/C.

That's a part of the loudness war... they make music more listenable with the most awful devices (cell phones, earbuds, car radios, laptop speakers), yet make it unbearably bad to anyone with a decent setup who expects quality.

If the game industry worked like the record one... every game would have GameBoy resolution, even if you ran it on a huge, hi-def TV set.

Re:Compression

[retchdog]

Very nice. I knew there had to be something like this; I'll check it out. Thanks.

Re:Compression

[4D6963]

Nah unfortunately it does it on the fly, and thus comes with an annoying delay.

Re:Compression

[Al Dimond]

Some people having crappy speakers doesn't mean that everyone's sound should be fucked up. What you want to do to the audio stream on your laptop makes sense if that's what makes it sound best; applying that on Google's side is ludicrous.

Re:Compression

[Yvan256]

A 1080p HDTV is 1920x1080 and the GameBoy is 160x144. That means each GameBoy pixel would be displayed on the HDTV as a 12x7.5 pixels block.

I don't know about you, but having anti-aliased pixels would piss me off!

It's what viewers crave

[Anonymous Coward]

Youtube, what bad audio compression you have!

All the better to hear the screams of yet another teenager lighting his farts (and himself) on fire, user.

Hans

[Anonymous Coward]

I upload already compressed FLV and find that the video has the same audio quality as I had encoded.

Brilliant idea though. hmm..I remember an episode of Batman Beyond where the Shriek used sound waves to destroy stuff and he even masked other waves. This is off-topic but maybe youtube compressor can be used as a weapon to increase the frequency to a point where glasses may break and dogs can be made deaf, hmm..

Re:Hans

[clang_jangle]

I upload already compressed FLV and find that the video has the same audio quality as I had encoded.

That definitely seems like it would be the best solution, but that's assuming niceone isn't already using flv for his uploads clips. Does youtube do more processing on an flv, even if it's submitted as "ready"? If you can present your material in such a way that no conversion is necessary on youtube's end, that will always give you the most control over the end result.

I remember being unhappy with the sound I ended up with years ago when my recordings got mastered to CD, but then I learned the way to beat that is to record digitally and master it myself. If you fall in love with the sound of a format you will end up disappointed unless the format in question is ubiquitous.

Ruff ruff!

[Tablizer]

mix in a high frequency sine wave (I used 19kHz) ... but is filtered out by the encoding process (so, no need to worry about deafening any dogs).

Ruff ruff rufff, and ruff rufff, you little bigoted ruff ruff ruffff.

-Tablizer's Dog
   

Re:Ruff ruff!

[4D6963]

Ruff ruff rufff, and ruff rufff, you little bigoted ruff ruff ruffff.

Translation : I'm ultrasound-deaf, you insensitive clod!

Re:Ruff ruff!

[Anonymous Coward]

I say I say I say How does a dog feel the morning after the night before?

Ruff!

Comment removed

[account_deleted]

Comment removed based on user account deletion

Brevity Required

[Tablizer]

Can someone post an example I could possibly listen to for more than one second?

No
     

Re:Brevity Required

[RealGrouchy]

CLICK THUD TICK SSSS No FWWWW CLUNK CLICK

I'm sorry--what did you say?

- RG>

A simple recipe

[Anonymous Coward]

1) Normalize sound around -15dBFS (RMS)
      (using the normalize-audio software)
2) Compress sound using the Dyson compressor
      (available in ecasound)

but is filtered out by the encoding process

[NovaHorizon]

you mean that high pitched squeal that is driving me nuts in the example more then the audio compression? Yea.. that's filtered out all right...

Re: but is filtered out by the encoding process

[Anonymous Coward]

Parent is rated "Funny", but...

I don't hear anything, but my ten-year-old daughter says that she can hear a high-pitched hum. She says it's especially noticeable before the music starts.

Re: but is filtered out by the encoding process

[AngryNick]

Damn you! I fell for your trick post about hearing the "high pitched squeal" and went back and listened again. I heard the hiss, but now the song is stuck in my head. ARGHHHH!!!

Re: but is filtered out by the encoding process

[NovaHorizon]

Over time, people usually tend to damage their ears a bit. Typically from the loud noises of a busy city, rocking out too much, or being in other situations that cause your ears to ring.

19KHz(what the article poster uses) is within the human range of hearing (20Hz - 20KHz.)

Using around a 35KHz sign would drive your dog nuts, but no one should be able to perceive it. (Assuming the compression doesn't drop the frequency any.)

Re: but is filtered out by the encoding process

[Theaetetus]

Over time, people usually tend to damage their ears a bit. Typically from the loud noises of a busy city, rocking out too much, or being in other situations that cause your ears to ring.

19KHz(what the article poster uses) is within the human range of hearing (20Hz - 20KHz.)

Using around a 35KHz sign would drive your dog nuts, but no one should be able to perceive it. (Assuming the compression doesn't drop the frequency any.)

You can't encode a sine wave that is higher in frequency than one-half the sampling frequency. This is known as the Nyquist frequency. So, at 44.1kHz sampling, your highest tone possible is 22.05kHz. At 48kHz, you're limited to 24kHz. Etc.

Even worse, using something over the sampling frequency will result in aliasing. Using a 35kHz tone with a 44.1kHz sampling rate will result in an audible 12.95kHz tone.

Warning from ccalam in the second video

[Looce]

The high quality version of the audio will have the 19 (or up to 22.1) kHz sine wave you choose to use in your video upload. So this is a trade-off of quality (high-quality = eek!) versus lack of unwanted range compression (low-quality = listenable, for lack of a better word).

FWIW, I can hear 19 kHz waves. So this trade-off affects me.

Re:Warning from ccalam in the second video

[4D6963]

Maybe they should try with infrasounds then?

Re:Warning from ccalam in the second video

[pz]

FWIW, I can hear 19 kHz waves. So this trade-off affects me.

You won't hear 19 kHz much longer. Seriously, not because of this or any other particular factor (although there are many), but because everyone experiences upper-range hearing loss as they get older, and it starts at an astonishingly early age.

Re:Warning from ccalam in the second video

[Anonymous Coward]

I'm 32 years old and i have no problems hearing very high frequencies. However the sound in the video does sound much lower than 19 kHz.

Re:Warning from ccalam in the second video

[cyclopropene]

You won't hear 19 kHz much longer. Seriously, not because of this or any other particular factor (although there are many), but because everyone experiences upper-range hearing loss as they get older, and it starts at an astonishingly early age.

I'm 34, which is not astonishingly young, I've been to my share of loud music concerts (though I use earplugs for the obnoxiously loud ones), and I can hear that 19 kHz pitch painfully loud and clear when the volume is turned up enough to hear the guitar. Perhaps I'm just astonishingly lucky with my hearing so far, but for me this is not a worthwhile tradeoff.

It reminds me of the old remote control TV my grandfather had when I was a kid which used high pitched sound that sent me running for the other room every time he changed the channel...

Re:Warning from ccalam in the second video

[Anonymous Coward]

All I can say is I'm about to turn 29, and I can still hear a TV that's on in another room to this day. High pitch whines in audio systems are easy to hear as well. Maybe mine will last a little longer since I work in the audio field listening for this stuff, and have become "trained" over time, but it's been something I've been able to do since I could remember

Re:Warning from ccalam in the second video

[jlkelley]

Age-related deterioration of high-frequency hearing may be a common experience, but as the previous posters prove, there's no hard-and-fast rule for when people lose certain frequencies.

As another bit anecdotal evidence -- I am 35 and can easily hear the 21 kHz sine marketed as audible by those "18 and younger" on the ringtone sites. I can also hear one particular kind of "ultrasonic" motion sensors, which is really annoying.

If the 19 kHz pitch suggested doesn't get filtered out, I would definitely find it unlistenable.

Re:Warning from ccalam in the second video

[Anonymous Coward]

Damn punk-ass kids don't appreciate the Intarweb anyway. Back in my day, you had to dial in uphill both ways in the snow just to download your puny porn images. Today, they call them "thumbnails".

Re:Warning from ccalam in the second video

[Anonymous Coward]

You would think they would strip all the sub/supersonic freqs, strip out one of the channels, etc., before compressing to keep the size down..

Re:Warning from ccalam in the second video

[Yvan256]

It makes the music sound like crap.

Re:Warning from ccalam in the second video

[Anonymous Coward]

So from that description, you must be between 10ish and 20ish.

As a rough rule of thumb, you'll loose about 1kHz every 10 years. The rate of loss is highly variable, but it will happen. A normal middle-aged mail upper frequency range will top out around 14kHz. Men loose their upper frequencies sooner than women.

Which even then it is still pretty good, considering a telephone starts topping out at 3 to 4kHz. Of course, a phone is bad for music, but those upper frequencies aren't that important for language. If you get a 7kHz phone, it actually starts to sound really, really good for voice, and almost acceptable for music.

Re:Warning from ccalam in the second video

[lawpoop]

People on the Autism spectrum, including people with Asperger's, are able to hear high-frequency sounds much better than the average person. I suspect there are a lot of such people on slashdot.

I worked with a guy once at a computer recycling place. He clearly had Asperger's, from the way his 'stories' were a list of facts delivered in a monotone, to his encyclopedic knowledge of model numbers and release years, to his inability to explain himself to anybody in charge. He could tell if a monitor was good or not by plugging it in and just hearing the tone that the transformer ( or whatever electrical component it was ) made. No need to plug it in to a video source or anything.

BTW, I downloaded all the tones at Free Mosquito Ringtones, and I was able to hear all of them, from 8 khz to 22 khz. ( Only 18 year olds or younger are supposed to be able to hear the 20+ khz ). I'm turning 30 this month; I suppose next month I won't be able to hear all of them. ;)

Re:Warning from ccalam in the second video

[pz]

It turns out that measuring hearing sensitivity is more challenging than one might initially imagine. I've worked in a lab at Caltech were some of the researchers worried about this and, well, I was surprised at how difficult it is to get accurate data. And at how easily we can be fooled by uncontrolled, informal experiments, like listening to a YouTube audio track processed through an unknown signal stream, played under non-ideal conditions through consumer-grade equipment.

If you've had your hearing tested in an audiology lab, then, assuming they did a proper job of putting you in an anechoic chamber and had blinded staircase tests with calibrated drivers, and they said that you had extended upper-range sensitivity, I'd be more inclined to believe that you're hearing 19 kHz. (It turns out I just had my hearing tested this past week, and although my hearing was normal at 9 kHz, they didn't bother testing anything higher; I was a bit disappointed by this.)

Although it is certainly possible to find a 34 year old able to hear 19 kHz, it is far more likely you're hearing an aliased tone at a lower frequency.

Re:Warning from ccalam in the second video

[ShakaUVM]

Ditto. I can hear a very high pitched whine coming from a muted television shut behind a wooden television door. What frequency is that? 20khz? 22khz?

My church uses a sort of teen repellent to keep deer away from the columbarium, but it drives me absolutely fucking nuts, since they leave it on during church services. After church, I literally run away from the building since the sound is so irritating.

I'm 30, and do have measured hearing loss from too many rock concerts.

But at the same time, I don't know how accurate hearing tests are, as the human brain isn't really calibrated to deal with the sorts of sine waves they produce in the tests.

Re:Warning from ccalam in the second video

[ShakaUVM]

>>People on the Autism spectrum, including people with Asperger's, are able to hear high-frequency sounds much better than the average person
>>BTW, I downloaded all the tones at Free Mosquito Ringtones, and I was able to hear all of them, from 8 khz to 22 khz.

I think you just diagnosed yourself!

Re:Warning from ccalam in the second video

[Anonymous Coward]

I'm 36 and I still hear 19kHz per testing, so, fail.

Re:Warning from ccalam in the second video

[musanim]

The high quality version of the audio will have the 19 (or up to 22.1) kHz sine wave ...

Actually not; it gets filtered out by YouTube's compression algorithm. Here's a demo video with spectrograms showing the audio before upload and as received from YouTube (after compression); you'll see that the sine tone is completely removed (though there are other distortion artifacts that are not).

Re:Warning from ccalam in the second video

[Anonymous Coward]

I am quite a bit older than 30 and I heard the 22khz tone easily. The 8khz tone kinda hurt my ears it was LOUD!

I'm glad that my hearing isn't messed up -- I like loud music but when it begins to distort or hurt the ears on playback its TOO LOUD!

Lack of Choices

[Tablizer]

It would be nice if YouTube offered some choices, such as volume adjustment, no volume adjustment, and also other things like stereo. The only way I know of to get stereo is to submit it in Adobe's proprietary formats. YouTube is pulling a Henry Ford: you can have any color you want, as long as its black.

Re:Lack of Choices

[4D6963]

It would be nice if YouTube offered some choices, such as volume adjustment

Yeah, I mean, who on YouTube would even think of abusing that?

Re:Lack of Choices

[Anonymous Coward]

Worked for Ford...

Re:Lack of Choices

[Tablizer]

[black paint] Worked for Ford...

By some accounts it was a sound strategy early on, as people were happy enough just to have a car that they didn't complain about the color. However, as time when on, some say Ford grew stodgy and stuck in his ways. This is partly why he never was able to follow on with a similar success, becoming just another car company.
         

Re:Lack of Choices

[Tablizer]

Yeah, I mean, who on YouTube would even think of abusing that?

If they "abused" it, it would be quieter, not louder. Who'd want to do that? There is a situation whereby they might trick you into lowering the volume, and then blast you with noise, but this is technically detectable. Whether they want to check for such is another matter.

     

Re:Lack of Choices

[MadKeithV]

"New!!! Volume enhancement pills for YouTube!" ;-)

Cheap asses

[Anonymous Coward]

While this is more along the lines of aural compression, my guess is that they're figuring out a good way to save some bits on the backend as well. If you can cut down the size of an audio track by a couple of percent, that's thousands saved in bandwidth costs over the millions of videos viewed per day.

This is something that I really find at odds with the nature of technological progress. When quality should always be improving, the bean counters ratchet things down over and over again to eke out extra $$. Once in a while, you get lucky, and a new technology allows for increasing quality at a lower cost.

As a side note, that Youtube video gets some really odd resonance out of my sub.

Re:Cheap asses

[4D6963]

And how exactly would that help making smaller files?

Re:Cheap asses

[MadKeithV]

If the compression setup makes sure that 50% of the lower dynamic range is never used, then you don't need to store it either.

Re:Cheap asses

[4D6963]

huh?? And why would it do that? You do realise that the compression talked about here makes pretty much everything loud, right? Therefore if you omit something it'll be even more noticeable.

Re:Cheap asses

[MadKeithV]

No, the point is that you never store the soft bits because there aren't any. You halve the storage space and add a fixed offset to every number that comes out of the data stream.
Say you start with 16 theoretical bits of dynamic range. You then compress the whole thing 2:1 and make-up gain it by 8 bits. You now know for sure that the lower 8 bits of your 16 bits are always going to be 0, void of information. So you stop storing them. Hey presto, half the space required!

Re:Cheap asses

[4D6963]

Man, what are you talking about. We're talking about STFT/MDCT based compressions, which is what YouTube uses. That means it stores frequency-domain bins, not samples.

As for what you talked about anyways, 16 bits sampling that only uses the upper 8 bits? What kind of compression formula would get you to that?

Re:Cheap asses

[MadKeithV]

2:1 Compression over the entire dynamic range with half the dynamic range in make-up gain.

Re:Cheap asses

[4D6963]

Is it like square rooting samples?

Nomalization standard?

[Waccoon]

It surprises me after all these years, audio formats don't provide recording information about the dynamics of the waveform.

Cameras write EXIF information into JPEG files, why can't we have something similar for audio so we don't have to adjust the volume all the time?

You don't have to be an audiophile to appreciate good audio. I have a custom amp next to my computer into which I've plugged headphones. Find anyone with a pair of headphones, and you'll find an amp, too. Either that, or a deaf person who's been tortured by a bad Flash file.

Re:Nomalization standard?

[4D6963]

It surprises me after all these years, audio formats don't provide recording information about the dynamics of the waveform.

Well what kind of things would you store that couldn't be obtained through analysis of the actual sound?

Re:Nomalization standard?

[dabadab]

There is such a thing (google for replaygain), but it's not about that, it's simple compression, i.e. making the really quiet sounds nearly as loud as the loudest ones.

Re:Nomalization standard?

[tftp]

All the things that you want to apply to the playback before the playback even starts, or even before the file is even fully downloaded.

Re:Nomalization standard?

[4D6963]

All the things that you want to apply to the playback before the playback even starts, or even before the file is even fully downloaded.

But in the case of YouTube they do all their processing on the entire file once and for all, so the point is moot.

Re:Nomalization standard?

[Orestesx]

Exactly, why do databases have indexes? All the information you need can be obtained by analyzing the data.

Re:Nomalization standard?

[tftp]

I was more thinking of YouTube doing no processing at all, and so that the client can apply its own if it wishes.

Re:Nomalization standard?

[Anonymous Coward]

It surprises me after all these years, audio formats don't provide recording information about the dynamics of the waveform.

You are mistaken. All of them do- it's the amplitude of the waveform as it is being sampled. The kind people at youtube just choose not to preserve those dynamics. Which is great for the umpteenth lip-sync video recorded on a handycam, of course- but not-so-great for those of us who actually provide reasonable quality audio.

Re:Nomalization standard?

[jimicus]

There is, in MP3 at least. It's used by mp3gain:

http://mp3gain.sourceforge.net/faq.php

However, not all audio players support it. I'm pretty sure the iPod doesn't, nor does iTunes. (For some reason iTunes does have a "normalise levels on all selected tunes" option but that works by decoding/re-encoding the audio, which is a lot slower because in addition to the audio analysis you have to re-encode the file and is likely to introduce further interference to the stream).

Having said that, I've only got a fourth gen ipod. For all I know, more recent models do make use of this tag and furthermore, for all I know if iTunes knows that it's being synced with an ipod which does support the tag then that's what it uses to adjust the gain.

Re:Nomalization standard?

[4D6963]

Except that these have a use, and that their falsifiability isn't an issue.

Re:Nomalization standard?

[Orestesx]

I was attempting to show, by analogy, that your statement taken at face value was negligent to the utility of metadata.

Re:Nomalization standard?

[4D6963]

OK, but I was talking about the very problem at hand here.

Re:Nomalization standard?

[Anonymous Coward]

Replay Gain is what you're looking for.

Re:Nomalization standard?

[Waccoon]

Intent. There's a reason why people "master" recordings.

It's called ReplayGain

[Anonymous Coward]

Read more http://replaygain.hydrogenaudio.org/.

Benefit of the doubt

[Anonymous Coward]

To give YouTube the benefit of the doubt here--it's possible that the sound modification is being done with good intentions.

Most YouTube videos are uploaded by amateurs with respect to the details of A/V. As such, the audio quality in many videos is probably low. It's also likely that the sound level between different uploads are radically different. This means that unprocessed audio would sound bad for many videos. Moreover, switching from clip to clip on YouTube would involve annoying changes in audio level (e.g. you turn up the sound for one video, but then the next one is painfully loud).

So, they may be automatically recompressing all the audio to fix many of the mistakes of amateur uploaders. Again, it's important to remember that YouTube is not really meant for distribution of high-resolution content.

Having said all that, I'm also not an A/V expert, so I may wrong on this. Also, it would be nice if YouTube gave some advanced options for more experienced people to use, so that they could flag their content for "skip audio recompression" or whatever. Also, YouTube's introduction of the "watch in high quality" option shows that they want to expand beyond low-res clips... in which case they need to provide commensurate audio quality.

first harmonic is at 10khz

[Anonymous Coward]

and humans can hear that ok
2nd is 5k and thats right in the mid band

or dont the geeks understand how sound works ?

Why don't they just NORMALIZE instead of compress

[Latinhypercube]

Why don't they just NORMALIZE instead of compress ? Compression changes dynamics, as in the thread descrription. Normalize would just raise the volume up to peak. No changing music, just increase volume...

Re:Just sneak past the entire recompression proces

[Not The Real Me]

"...Wouldn't another solution be to sneak past the entire recompression process by submitting a .flv video..."

Last time I submitted a video, about six to eight months ago, Youtube did not accept .flv or .swf formats, even though that is the format that they use to stream. Youtube wanted mpg, divx or mov formats. That sucked because my original was done in swf. First I had to convert the swf to divx which I uploaded to Youtube. Converting from swf to divx resulted in a big quality degradation. Youtube then converted the divx back to flv which resulted in a second quality degradation with the audio being completely out of sync with the video.

first harmonic of what?

[unfunk]

What you just said makes no sense.

The first natural harmonic of a 5kHz tone would indeed be 10kHz, but the second would be 20kHz, and so on.
Every sound has a whole raft of natural overtones and harmonics, individual to itself. A 1kHz tone's harmonics are at 2kHz, 4kHz, 8kHz, etc. It's therefore really quite disingenuous to just state that the "first harmonic is at 10kHz"

Re:Just sneak past the entire recompression proces

[Anonymous Coward]

That would be a mess, though it couldn't be much different than what they currently do. They could simply accept finalized flv files and put out-of-spec flvs in the encoding chain with the rest of the uploads.

The cat got my tongue

[darklich14]

Brilliant! I've heard about problems with "normalizing" in the past. This is an excellent way to work around this problem!

Choose better.

[jbn-o]

Host your video somewhere else, upload it in a high-quality format, and let the site make derivatives for you (including a Flash video and a player you can embed in your webpage if you insist on placating a proprietor). Some organizations do this daily and it works excellently. YouTube needs you more than you need YouTube.

Re:Choose better.

[Jesus_666]

Is there some kind of listing that compares the various video hosting services? Something where I'd find "audio compression" as a column in some matrix with values like "no", "yes, automatically" and "yes, user-configurable"?

Re:Choose better.

[jbn-o]

I don't know of such a thing, but I can address some of those concerns with regard to the Internet Archive—I do know that the Internet Archive will (by default) derive video and audio files for you. If you don't like anything it derives you can hide the file so it's unavailable for download. If you want to add to the collection of files under an entry, you can also do that.

I suggest uploading the highest-quality source material you can and letting IA derive and host lesser files. So upload 24-bit FLACs, WAV, or AIFF files and let IA make Ogg Vorbis and various MP3 files for you. Upload MPEG-2 broadcast-quality movies and let IA make Ogg Vorbis + Theora, Flash, and other movie files for you. Then always link to the "download" URLs (BBB DVD ISO in NTSC format, for instance). Never link to the redirected URL because IA may need to move things around and it will keep the download URLs up to date for you.

I'm doing these things with the Big Buck Bunny entry: as I get more BBB stuff, I add to the entry. Some of the files the system made were unnecessary and derived from files it doesn't understand (like making animations from ISO DVD images).

I seriously see no reason to host with YouTube when IA is so generous in its hosting. Most people won't care where the movie comes from, only that it can be viewed easily. IA does that and far more desirable stuff for you gratis.

Teen Buzz/Mosquito Ringtone

[Looce]

I have indeed heard of such deterioration on the Teen Buzz website (which is currently down for excessive bandwidth usage?) - but this page describes it as well.

Those little annoying sine-wave sounds are also used by TV advertisers such as Kentucky Fried Chicken to grab teens' attention if adults are not their market. (For the record, if you can't hear the tone, it sounds off when the KFC bucket shows up.)

Re:Teen Buzz/Mosquito Ringtone

[flink]

I'm 30 and I heard that loud and clear, and I have been to many, many extremely loud hardcore shows in small clubs with now ear protection. (In my youth of course, I'm a little more careful with my ears these days).

Re:Teen Buzz/Mosquito Ringtone

[macslas'hole]

I'm 41 and I hear that plain as day! I'd be surprised if its more than 15 kHz.

Re:Teen Buzz/Mosquito Ringtone

[funkatron]

I can hear that but it doesn't sound all that high

Re:Teen Buzz/Mosquito Ringtone

[Anonymous Coward]

I'm 29. That 19khz drives me nuts. Expected hearing loss is not working as designed.

Re:Teen Buzz/Mosquito Ringtone

[Prune]

Huh? This sounds somewhere in octave 7, so it's not even 4 kHz. 19 kHz my ass.

Re:Just sneak past the entire recompression proces

[4D6963]

Ha... however considered that .flv video is H263 (or is it H264 now?) I guess you could find a program that would change the container to an AVI-compatible one and thus avoid recompressing?

reminds me of tape bias

[stevetures]

hopefully this wont date me much, but this reminds me of tape bias, the high-frequency signal applied to the magnetic frequencies used to record tapes (oh it did have unintended consequences). http://en.wikipedia.org/wiki/Tape_bias

Thank the iPhone

[wiredlogic]

I would guess they are doing this to better "service" handheld devices like the iPhone and upcoming Android devices that have limited dynamic range in their speakers.

Re:Thank the iPhone

[adpowers]

Google already creates a different encoding for iPhone (H.264) since it can't play Flash videos. If they are doing this for the iPhone (which I have a hard time believing), why don't they only do it for the files destined for the iPhone?

Kompressor crushes you (tube)!

[dzfoo]

Sorry, couldn't resist.

        -dZ.

Re:Kompressor crushes you (tube)!

[Anonymous Coward]

K is for...

Recording vs Processing

[rueger]

Although I tend to think that Dan East summed it up best, I feel the need to point out that 95% of bad YouTube audio is the result of lousy recording quality, not subsequent processing.

Garbage In, Garbage Out.

The mics and electronics on most consumer camcorders (or that most people use with their Macs and PCs) are just plain crappy, and shouldn't be relied on for anything that you hope to distribute. And of course, some actual audio recording skills help too.

Re:Recording vs Processing

[DNS-and-BIND]

Oh yeah, hold on, let me go spend a couple hundred dollars on microphones for my camcorder. Great idea. As a matter of fact, why don't I go ahead and upgrade that all-in-1 camcorder for a pro kit, take some filmmaking classes, just so I can put videos of my sister's wedding on Youtube. Great idea there, hoss.

Re:Or you could remodulate

[4D6963]

I didn't realise that what I said sounded impressive to the point of prompting a trekkie (or whatever it is you're referring to) to deblaterate nonsensical gobbledegook to try to sound as "cool".

Just don't use Youtube

[Snaller]

Use http://vreel.net/ instead - its divx, better quality anyway.

KFC tone is 4825 kHz

[Derling Whirvish]

I measured that KFC tone at 4825 kHz with a spectrum analyzer. It's not very high at all -- certainly not the mosquito tone.

Re:Or you could remodulate

[Yvan256]

You forgot to mention holodecks, time travel and alternate universes.

Oh, and have the Borg assimilate it all just to mess things up a bit.

What, no Rickroll?!

[rumli]

I clicked the YouTube links with an eager tingle in my spine. Very anticlimactic.

This is...

[Anonymous Coward]

..some people with asthma heard just fine up to 30K! They need to go to more rock concerts - sit by the speakers. That will cure it. I can barely hear over 8K myself!

Re:Or you could remodulate

[Anonymous Coward]

He's probably a Digg user. Those guys are almost, to be generous, as dumb as the YouTube commenters...

Who's the idiot at Google...

[SmoothTom]

...who decided to brute-force modify each and every copyrighted audio track on YouTube (every audio track) without permission from the copyright owner?

Destroying the dynamic range intended by the originator in this manner is not acceptable.

If Google feels that some audio needs "normalization" or whatever they wish to call it, at least make it a feature that can be opted into by the owner of the video...

--Tomas

19KHz? Why not 1Hz?

[groovelator]

How about using a very low frequency sound, say 1 Hz? Or a Square wave with a period that is the same length (or greater) as the clip in question? Maybe that way you could avoid the re-encoding / aliasing issues.

Many compressors not affected by 19 KHz sine wave

[iliketrash]

Many modern compressors (aka compressor/limiters) use multiple frequency bands, typically four or more. The compression is done separately in each band with the results re-combined into a final result. One of the reasons for processing multiple bands is to eliminate pumping in which large dynamic range variations in one band modulate other sounds in inverse fashion--the thumping base causing the female singer's voice to fluctuate in level, for example. Although it is impossible to get heavy dynamic range compression without some degree of this effect, some versions are a bit more discreet about it.

Adding a 19 KHz sine wave would work only to defeat the upper band of a multiband compressor. If this approach works on YouTube it is because they are using a one- or two-band compressor.

Heavy compression ruins virtually all popular music in the form in which it is released. Further compression e.g. by FM radio, internet streams, and YouTube, ruins it a little bit more.

For an interesting discussion of how one artist is pissed off about all of this, Google for Bob Dylan and dynamic range compression.

I hope

[Anonymous Coward]

I hope that guy didn't actually think that anyone would listen to his whole sone. Man I don't know if the music or crappy compression was worse. I made it about 5 seconds into each recording....

What happend to do no evil?

[TheNetAvenger]

What happend to do no evil?

Oh, right, it doesn't apply if it allows them to save money...

Meet Google, the next Microsoft, this time a scary version with enough information on all people to keep them in jail or quiet. Love the data mining! Go GMail, Go Search, Go Ad clicks, Go Firefox reporting back...

Yeah Google!

Don't reduce the quality!!

[suck_burners_rice]

Duh, I think it really sucks that YouTube is doing this. I think that all videos should be in high-def H.264 and if they come in at a lower quality, YouTube uses Google's massive server farm to extrapolate, using math, AI, and other methods, the missing data, a la the computer in Star Trek that can remove a person from a picture who is obscuring someone standing behind that person, then extrapolate the missing information to show that person's face, even though there is no possible way to do that (except in a television series). So you'll be able to upload a JPEG image that has been compressed to such an extent that it appears as one solid color, and YouTube will turn that into the full 220 minutes of Cecil B. DeMille's The Ten Commandments (the 1956 version, not the 1923 silent version). I don't know how that could possibly happen, but this is Google we're talking about.

Need proof

[GWBasic]

So I tried these videos on three different playback mediums:

• Macbook Pro, 17" w/ the big speakers, Recent FireFox: No audible difference; although the speakers aren't big and powerful enough to get anything spectacular.
• Fancy Home Theater, Windows XP, Optical fixed at 44.1khz, IE 7: Subtle difference, the "better" one sounded a little quieter, although I wouldn't describe the original as "mangled" or over-compressed.
• Fancy Home Theater, Wii (Opera), Analog with DSP: Again, a Subtle difference just like my experience with XP. The "mangled" one was slightly louder, but this could be attributed to YouTube applying normalization.

In all cases, the differences observed were too subtle to demonstrate the claims. Yes, the first video was louder, but the difference can easily be attributed to volume degradation by the post-processing performed on the second video. The placebo effect can play a big part in these comparisons.

The only way to prove what YouTube is doing to sound is to rip the audio and compare the waveform with the original. These videos do not prove the poster's claims.

Re:Need proof

[g-san]

To you. These videos do not prove the poster's claims, to you. You should probably go clean your ears, because if you can't tell the difference you probably have years of wax build up in there. Or you just don't have an ear for this sort of thing, so are not qualified to comment. People have examined the waveforms, RTFT, and this is happening.

Re:Need proof

[GWBasic]

You should probably go clean your ears, because if you can't tell the difference you probably have years of wax build up in there.

I just had them cleaned out a few weeks ago. (The ironic thing is that it was YouTube videos of people digging huge chunks of earwax out of their ears that prompted me to do it.)

I didn't use a loud volume when I compared the two videos. I'm not doubting that YouTube is in some way altering the audio; however, an A-B comparison between two YouTube delivered videos really can't provide an accurate example of the distortion, because both videos are subject to the same distortion. I'd really like to see images of waveforms.

Re:Just sneak past the entire recompression proces

[evilviper]

Last time I submitted a video, about six to eight months ago, Youtube did not accept .flv or .swf formats,

Youtube has accepted flvs for quite some time now. That does not excend to SWFs, however. Animations are not videos, and can't be converted easily.

Youtube == waste

[Anonymous Coward]

So let me get this right, you're complaining that youtube compands audio? You're probably the same bunch who upload videos with heavy macroblocking and the wrong aspect ratio, and you're worried about companding the audio?

Re:Just sneak past the entire recompression proces

[evilviper]

Ha... however considered that .flv video is H263 (or is it H264 now?) I guess you could find a program that would change the container to an AVI-compatible one and thus avoid recompressing?

The original Flash video format is Sorenson Spark. It's based on H.263, but incompatible.

H.264 and AAC don't fit in an AVI well at all... It's possible to do, but it's a mess, which most apps don't properly support.

In either case, I don't believe for a second that YouTube's video conversion is smart enough to detect compatible video or audio encodings in a different container, and remux rather than reencode.

Despite what the parent said, however, you can encode properly formatted, fully compatible FLVs to youTube, and they will be published, unmodified.

infra- rather than super-sonic?

[dltaylor]

Particularly if you use the "brown noise" at high volume. That would give additional meaning to "garbage in, garbage out".

Re:infra- rather than super-sonic?

[old and new again]

you mean brown note i guess as the brown noise is just a type of noise, as is pink, white, blue, etc.

Re:infra- rather than super-sonic?

[Anonymous Coward]

I always thought brown noise was the reverberation one hears in a bathroom after a bean meal.

Re:Correction KFC tone is 4825 Hz

[Derling Whirvish]

Oops, sorry. The KFC tone is 4,825 Hz or 4.825 kHz. Damn them decimals!

Re:Just sneak past the entire recompression proces

[old and new again]

youtube reencodes any flv now, before you uploaded an flv with a total bitrate under 350kbps and it WASN'T re encoded, thus stereo sound, they re encode EVERYTHING now, even a 100 kbps total flv was re encoded

It isn't YOU(tube) if they modify the content.

[joocemann]

From my understanding, the concept of YouTube is to put your personal audio/video recordings online for people to view.

I understand how they may re-process videos so they stream well (limiting size, etc). And how audio may be re-processed as well to stream easily, which is called Compression (but not the same term as we are discussing).

The fact that YouTube is applying, not a quality/size modifier, but a SOUND modifier, is something to be concerned about. Essentially, the sound you are getting from these videos is not (relatively) the same as it was when it was recorded and uploaded.

I am kind of thinking of a chili cooking contest where all submissions, unknowingly, have a tablespoon of salt or MSG added. Thats not the same as serving less (downsampling).

YouTube should recognize this problem and do the right thing by removing the limiter/compressor and letting the audio remain as natural as it was when it was recorded. Or they could call it SomeWhatYouTube.com....

*** I kinda wish the author of this one had made more clear the difference between compressing audio file size (like making an mp3) and compressing audio with digital/analog tools/gear for the purposes of making softer sounds louder. The terminology may confuse people who are not sound-boys.

Although a form of compression...

[xjesus]

The more common term for this type of audio processing is referred to as AGC or Automatic Gain Control. A good number of camcorders have this built in already. It sounds like the issue with the youtube implementation is that the max gain allowed is just too much and the attack rate (for gaining up) is way too fast. Artistically they should allow you to turn it off or adjust the parameters, otherwise they just made all new music on the site sound bad.

Classic compression, on the other hand, is when the loud stuff is made quieter but the quiet stuff stays quiet. If you plot an input level vs output level you get a 'knee' where the threshold for compression begins. The angle of the knee is determined by the ratio of compression.

AGC is like someone has the volume knob and cranks it up so that you can always hear something regardless of the content. Usually there are minimum thresholds and max gain settings to go along with this to adjust issues such as these.

Normalizing is yet another technique which requires non-realtime analysis of the entire piece to determine and set a single gain setting for the entire file; a sort of best fit gain.

And from the more complex end, there's Dolby Volume which incorporates several of the above features with their own 'special sauce' in an attempt to provide uniform listening levels between sources and content. I haven't heard it yet to know if it is any good.

-david

Speakers?

[Anonymous Coward]

I don't think its YouTube that is the problem, It's your speakers...

compressed classic music

[r00t]

imagine going to see a classical music concert and the entire concert is played at the exact same volume, no crescendos or decrescendos

Sweet! Mozart might be tolerable, or even rather nice.

The number one thing I hate about typical classical music, particularly Mozart, is that I have to keep adjusting the volume knob while it plays. It's either deafening or inaudiable.

Re:compressed classic music

[pipoca]

Listen to it in a quiet enviroment, like what it was meant to be played in. If you have to jack up the volume to hear the quiet bits over the general noise, of course the loud bits are going to be deafening.

Re:compressed classic music

[r00t]

I doubt it was meant for a quiet environment.
AFAIK, it was meant for a real live audience.
People cough, chat, squeak their chairs...

I don't know where I'd get a quiet environment.
Supposing I had one, I wouldn't want to just sit
there waiting for the music to finish. Ugh. I have
better things to do with my life.

In any case, that still wouldn't fix it. It still
would have way to much of a difference.

It's possible that Mozart never intended to have
such extremes. Modern recordings may be just bad
because orchestras want to show off how much
dynamic range they can manage, even at the
expense of the music.

Look at the spectrum yourself in real-time..

[Sidn]

..using e.g. http://softsolutions.sedutec.de/audioanalyser.php (Windows only)

Any hints to a similar tool for Mac OS X or Linux would be greatly appreciated!

Re:Just sneak past the entire recompression proces

[Bazer]

You can upload flv's but youtube will re-encode them if the average bitrate is higher than a certain, very low threshold (something like 350kbps total) and you won't get a high quality encode.

Aliasing

[Theaetetus]

After some more testing it seems that there is a problem with high quality mode. With the tone and sample rate I used (19kHz and 44.1k) at least the high quality encoder whistles at, some other frequency. Sounds like somewhere less than 10kHz to me.

From your description (and the article's mention of a 16 kHz limit), it sounds like they're actually sampling at 32kHz, which would give a Nyquist frequency of 16 kHz... If they don't have an anti-aliasing filter (because they've only been around for 40 years, so it's understandable that Google couldn't use a search engine to learn about one), then a 19 kHz tone will alias around the Nyquist frequency and end up at 13 kHz.

Try doing a 16 kHz tone instead, and see if it goes away. Also, make sure you're using a sine wave rather than any other type - you don't want higher harmonics in there.

ScrewTube

[DustoneGT]

I use Vimeo for everything these days. I can't impress clients with their horrid quality.

Re:Or you could remodulate

[bigstrat2003]

Well, I assume that everything you said had meaning, but to someone who doesn't know anything about audio (like me, and presumably the AC), it really does sound like Trek-worthy technobabble.

Longer sample, and test (was Re:This hurts)

[musanim]

I ran into this problem in a big way when I posted this. There are many places where the limiting is creating distortion (especially in the right-hand chords), but the worst is at about 6:46. If you start at about 6:30, you'll get the full effect when you reach 6:46 --- OUCH!!!

I made a test video that shows that the technique of mixing in a high-frequency tone (I used 20 KHz, in a 48 KHz file) works. The original distorted version is at 0:04 and the same with the distortion eliminated with the addition of the tone is at 0:23.

Re:Longer sample, and test (was Re:This hurts)

[Compuser]

Somebody mode parent up. I am not a troll. I asked a serious reasonable question and thankfully, I got a meaningful answer now.

Re:Just sneak past the entire recompression proces

[Anonymous Coward]

FLV is not a supported format.

Bemused.

[Profesh]

I operate a marginally popular music-channel on Youtube (http://www.youtube.com/user/Profeshian), and have decided against further uploads until such time as when this utter travesty has been lain to rest. Hopefully my upwards-of-1,300 subscribers will understand.

Demo of YouTube distortion and 20KHz workaround

[musanim]

Okay, here's a video that will give you a quick sense of what the YouTube compression/clipping distortion can sound like and what the effect of the 20KHz sine-tone workaround is; the audio is accompanied by before/after spectrograms showing (a) the "spectral splatter" of the distortion, (b) the filtering out of the 20KHz sine tone during compression, (c) the reduction of the spectral splatter distortion, and (d) other distortion artifacts that are not removed with this technique (they look like a reflection of low-frequency energy, so they're probably Nyquist-related aliasing).

If you want to hear this music in context, it's from this video at around 6:46.

Youtube: Encapsulate, Don't recompress.

[Anonymous Coward]

I am an anime fan.

I put a AMV up on YouTube.

The YouTube version was re-compressed into a smaller file which caused the A/V quality and synchronization to suffer. The input file doesn't have this problem.

Therefore I think YouTube is doing this to appease the media cartels for all the infringement going on on YouTube. But won't the same thing happen to 100% original content as well? It shouldn't!

Re:Check example of youtubes sound problem

[Anonymous Coward]

check my video and remix that its killing the hell out of, i pulled down the overall volume by -3db but still no joy check it out for an example....
youtube.*com/watch?v=hmO92x3L-hI

then goto myspace*.com/a2osound to see myspaces version