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Why Distributing Music As 24-bit/192kHz Downloads Is Pointless
An anonymous reader writes "A recent post at Xiph.org provides a long and incredibly detailed explanation of why 24-bit/192kHz music downloads — touted as being of 'uncompromised studio quality' — don't make any sense. The post walks us through some of the basics of ear anatomy, sampling rates, and listening tests, finally concluding that lossless formats and a decent pair of headphones will do a lot more for your audio enjoyment than 24/192 recordings. 'Why push back against 24/192? Because it's a solution to a problem that doesn't exist, a business model based on willful ignorance and scamming people. The more that pseudoscience goes unchecked in the world at large, the harder it is for truth to overcome truthiness... even if this is a small and relatively insignificant example.'"
I know, Stephen Colbert is Reddit's hero and they're starting to infiltrate this site as well, but seriously. Call them lies. That's what they are, that's what they -deserve- to be called. Are people really that passive-aggressive and afraid of expressing themselves that they won't call someone who lies a liar any more?
Does it matter when the dynamic range is shot to hell?
lossless formats and a decent pair of headphones and a set of really expensive MONSTER CABLES will do a lot more for your audio enjoyment than 24/192 recordings.
There, ftfy.
I record my performances at 96 kHz sample rate, I have to say that the music sounds much better at 96 kHz than 48 kHz I think (feel?) because the higher sample rate gives audio effects like reverb a lush, deeper sound.
The more sample units per second give the effects more to work with, in addition, even though you can't hear above and below certain frequencies recording those inaudible frequencies has an effect on the final product.
You may be able to find some scientific proof of this but for me it's an ear thing, higher sample rates sound better.
"If any question why we died, Tell them because our fathers lied."
I find your well-reasoned and respectfully written response to be full of helpful counterpoints and useful references. I wish to subscribe to your newsletter.
>There is a huge problem with file sizes
Not any more, pumpkin.
We hit the terabyte size in drives a couple of years ago. There's no reason to be buying this format vs "archive quality" cd-audio or other lossless.
Buy/rip lossless. Transcode to lossy as needed. Anything else and you're being ripped off.
I listen to real music with real instruments. The "swish" you get in high-frequency percussion with lossy algorithms is annoying as fuck.
--
BMO
You are missing the point of the article. 192KHz is not 192kbps.
Double blind test results or I will continue to believe that you are suffering from Illusory superiority.
-1 overrated isn't the same thing as "I disagree".
I have a PhD in Digital Music Conservation from the University of Florida. I have to stress that the phenomenon known as "digital dust" is the real problem regarding conservation of music, and any other type of digital file. Digital files are stored in digital filing cabinets called "directories" which are prone to "digital dust" - slight bit alterations that happen now or then. Now, admittedly, in its ideal, pristine condition, a piece of musical work encoded in FLAC format contains more information than the same piece encoded in MP3, however, as the FLAC file is bigger, it accumulates, in fact, MORE digital dust than the MP3 file. Now you might say that the density of dust is the same. That would be a naive view. Since MP3 files are smaller, they can be much more easily stacked together and held in "drawers" called archive files (Zip, Rar, Lha, etc.) ; in such a configuration, their surface-to-volume ratio is minimized. Thus, they accumulate LESS digital dust and thus decay at a much slower rate than FLACs. All this is well-known in academia, alas the ignorant hordes just think that because it's bigger, it must be better.
So over the past months there's been some discussion about the merits of lossy compression and the rotational velocidensity issue. I'm an audiophile myself and posses a vast collection of uncompressed audio files, but I do want to assure the casual low-bitrate users that their music library is quite safe.
Being an audio engineer for over 21 years, I'm going to let you in on a little secret. While rotational velocidensity is indeed responsible for some deterioration of an unanchored file, there's a simple way of preventing this. Better still, there have been some reported cases of damaged files repairing themselves, although marginally so (about 1.7 percent for the .ogg format).
The procedure is, although effective, rather unorthodox. Rotational velocidensity, as known only affects compressed files, i.e. files who's anchoring has been damaged during compression procedures. Simply mounting your hard disk upside down enables centripetal forces to cancel out the rotational ruptures in the disk. As I said, unorthodox, and mainstream manufactures will not approve as it hurts sales (less rotational velocidensity damage means a slighter chance of disk failure.)
I'd still go with uncompressed .wav myself, but there's nothing wrong with compressed formats like flac or mp3 when you treat your hardware right
--
BMO
> I listen to real music with real instruments. The "swish" you get in high-frequency percussion with lossy algorithms is annoying as fuck
Seconded. Many things sound fine (not great, but OK) in medium to low bitrate MP3 or OGG or AAC or whatever. Some things sound terrible, and when they do, it sucks to listen to.
As a former audio engineer with some ranking success, I can tell you that it's true -- delivering high-sample rate audio as an end format is really pointless. It hardly makes sense in a studio, and definitely is illogical for the distribution of a final mix.
However, there is an increase in quality using 24 bit. Most people just assume increasing the bit depth is the same as increasing the sample rate, but this is incorrect and short-sided. With higher bit depths, you can get your analog components operating a little further away from the noise floor. This also makes dithering much less noticeable (the noise you hear when you crank the volume up as a song fades out). Why? There are more "levels" for each sample to be recorded into. It's like going from 16 to 24 bit color. You would notice this.
For the 192 KHz fans out there, there is direct and proven mathematical reasoning for why 44 KHz audio is plenty. That, and your equipment probably can't produce it. Your converters probably suck at this frequency, and your ears definitely can't vibrate that quickly. More samples doesn't "smooth out" the waveform.
When you can tell the difference between 44.1/16 and 192/24 in a double blind trial, come back and we'll talk.
Subjective opinions about audio quality, particularly those accompanied by words like "deaf" or "idiot", are worse than useless. Subjective listening is deeply suggestible and unreliable. Claimed differences among any acceptably well designed audio electronics virtually always disappears under rigorous and controlled testing.
To give just one example, listeners reliably prefer the louder source in subjective testing, even if the difference is not consciously perceptible. If a 192/24 D/A is just 0.1db louder than a 44.1/16 source, listeners will tend to describe it in all sorts of subjective terms... "edgier," "richer," "more forward," "cleaner impact," "deeper soundstage" etc when in fact it is simply a little louder.
If you buy your music over the 'net, flac isn't an option, and CD stores are dying. One of the many reasons piracy is still so popular among audiophiles.
"People don't want to learn linux" hasn't been a valid excuse since '03.
http://en.wikipedia.org/wiki/Nyquist_frequency
Were that I say, pancakes?
"Because it's a solution to a problem that doesn't exist, a business model based on willful ignorance and scamming people."
which happens to be a business model that works, unfortunately
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Your cat is not "listening", it is simply tolerating that annoying racket that you call "music" in exchange for food, body heat, clean kitty litter, etc.
If you're sure you can hear a difference, why don't you ABX and prove it (or give strong evidence for it)? It's easy to hear a difference if you think you're supposed to, or if you paid a lot of money for speakers, etc. But its a lot harder to hear differences if you're doing a double blind test.
It's certainly OK to allow your emotions to take over if it makes you feel better to know you're listening to 24/192, but that's different than there actually being a perceived difference. You feeling better listening to 24/192 is an opinion, but whether you can actually perceive a difference is fact; lots of people confuse the two, so don't feel too bad.
Either Harry Nyquist or Claude Shannon probably could have. But they are both dead now. So we will have to take Monster Cable marketing department's word for it now.
Have gnu, will travel.
Did you listen to it double blinded? No? Then I don't care what your confirmation bias tells you that you heard. The difference is beyond your ability to hear, but not beyond your ability to deceive yourself into believing what you want to believe.
-1 overrated isn't the same thing as "I disagree".
A group of sixty audio professionals and audiophiles did a series of controlled double blind trials published in the Journal of the Audio Engineering Society. They found no perceptible degradation caused by a 16-bit/44.1kHz A/D/A.
http://www.aes.org/e-lib/browse.cfm?elib=14195
The Nyquist-Shannon Sampling Theorem basically shows that if an analogue signal contains no frequency higher than B Hz then sampling at any rate greater than 2B Hz is adequate to reproduce the signal without aliasing. In the case of audio recording intended for the human ear, the highest audible frequency is about 20kHz and the minimum sampling rate to cover that should be 40kHz. This is (partly) where the 44100 HZ sampling rate of CD audio comes from. In practice sampling is usually performed faster than required by the theorem (though not four times faster). The theorem is not sufficient in itself to guarantee perfect reproduction and is limited by the ability of real systems to match the mathematical ideals during sampling and reproduction. Reproduction is, however, typically very close.
The 192kHz sampling that is the subject of this thread is capable of capturing frequencies well beyond the capability of a human ear to hear, or any typical speaker system to reproduce.
Patent litigation: A doctrine of Mutually Assured Destruction... in which everyone seems willing to push the button
No loss from the original sampling, i.e. they didn't loose any information in the compression. Most music is sampled at (correct me if I'm wrong someone?) 44kHz, I forget how many bits, I think 16. The thing being touted is sampling it at 192kHz with 24bit resolution, which is much higher on both counts, and therefore, in theory, should produce better quality reproduction of the sound based on oversampling and reduction of the signal to quantization noise rate. The point the TFA makes is that human ears can't hear the difference, although I think that some audiophiles may beg to differ.
FWIW, I have quite bad ears, a recording needs to be quite bad before I notice it. I'm an electronic engineer though, so I know all the theory...
One thing I know, and that is that I am ignorant...
You mean like, honkies, spics, niggers, dune coons, prairie niggers, kykes, faggots, chinks, canucks, wops, guineas, krauts, and polocks? I think that's everybody anyway, my apologies if I left out any group, I try to be an equal opportunity offender, challenging people to be adults and get over their group identitied. Criticism welcome. Cowardly disapproval spurned.
I know, Stephen Colbert is Reddit's hero and they're starting to infiltrate this site as well, but seriously. Call them lies. That's what they are, that's what they -deserve- to be called. Are people really that passive-aggressive and afraid of expressing themselves that they won't call someone who lies a liar any more?
Okay, everybody, listen up: Anonymous Coward is having a rough day so let's all be extra nice to him!
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
> If you can't hear the difference ...
I certainly can. I'm glad to hear others say that, too. I thought it was just me.
We have an analogous problem in broadcasting -- everyone wants to use compressed formats to save space and upload/download time. Files are thrown all over the Web now. (I haven't seen a reel tape in years, though I think we still have an old reel-to-reel somewhere just in case. Political season coming up, after all.)
The problem is REALLY bad when you repeatedly encode. For example, our digital automation systems wants to compress files. Our studio to transmitter links (STLs) want to compress to save bandwidth. HD Radio compresses the SNOT out of the audio. Honestly ... some of the crap that I hear on the radio now is so bad I don't know how anyone can listen to it. It swishes, it glitches, it swarms, it sounds brittle, it's awful.
I made a rule in our facilities a few years ago that if it wasn't at least 256 Kilobits, we wouldn't air it. This annoyed some people -- one guy had to dump and entire music library that he'd spent a week putting into the system -- but it was awful.
Maybe there's no point in 192/24 for kids listening to pirated music on $20 MP3 players, but I refuse to believe that most people can't hear the difference. Heck, I'm getting old and I'm half deaf nowadays, and I can immediately hear the difference. There's just no comparison.
Cogito, igitur comedam pizza.
For the rest of us on /. haven't we had all of our music in FLAC for a decade now? I don't even listen to music much and mine is.
My music is mostly stored in whatever the default is for YouTube videos that I've saved locally. I'm apparently even less of a music fan than you are.
Fun fact: I'm also an audio technician. Yes, I can hear the occasional damaged sound, but I'm not enough of an asshole to care.
You do not have a moral or legal right to do absolutely anything you want.
There may be no theoretical benefit, but since there's no such thing as an ideal sampler or filter or quantiser, it has many practical benefits.
One thing I know, and that is that I am ignorant...
Truthiness refers to a specific kind of lie-- a lie that sounds true, and that a large segment of people really want to be true. The kind of thing that's close enough to true for AM radio talk show hosts.
And now... I'll get off your damned lawn. Don't forget to take your teeth out before falling asleep.
Not if you don't know any better. ;-)
Seriously, its been so long since I've seen a live band I don't know what a drum is supposed to sound like.
At my age my ears are not so hot.
Sig Battery depleted. Reverting to safe mode.
The point is that the 44KHz 16bit track has already been compressed from the original recording. However you rip that track, lossless or lossy, it doesn't matter; you're still not getting the original track.
Knowing this, it doesn't mean that the tracks some sites are selling as 192KHz 24bit are from the original sources, or will even sound better, either. The original track could have been recorded with bad equipment or settings. In other cases, when doing comparisons on CD tracks vs high resolution tracks from sites like HDTracks, you can sometimes find that the HDTracks track is just the CD track with increased reported resolution/file size - possibly due to the inability to acquire the original material, though it could also be as simple as pure greed and laziness. Not that all of the albums on those sites are fakes, but a few of them have been found to be ripoffs.
There's also the fact that it's extremely unlikely anyone can tell the difference between an encode at 96KHz vs 192KHz. If they are both properly encoded from the same source, it's unlikely there will be any audible difference between them.
Indeed. One of the overlooked but highly important issues with sampling rates is that although you can represent up to Nyquist in a periodically sampled signal, that is the limit for infinite length recordings. For finite-length recordings, it isn't all or nothing, represented perfectly or not at all -- instead the uncertainty (read: representation error) increases as you approach Nyquist.
Too bad Shannon and Nyquist are dead. It seems they've completely misunderstood the math. How embarrassing they passed on before you could correct their mistake. Now they'll never know.
I used to think like you. Spent thousands on audio equipment.
Now that I'm deaf in one ear I listen to MP3s through $24 headphones.
Being deaf saves a lot of money.
This space available.
If George Carlin were still alive, he would mod you up right now.
Double blind test or gtfo. The peer reviewed research says you can't hear it. Talk is cheap, show us some data.
-1 overrated isn't the same thing as "I disagree".
There is a huge problem with file sizes (so both hard drive space and download bandwidth) with lossless files, so no, it's not entirely without problems.
I own (legally, even) somewhere on the order of 2500 CDs.
I have ripped all of them to FLAC (lossless).
Total size, under 600GB. I could easily fit my entire collection on a single HDD five years ago. Today, they don't even count as the biggest single directory on my home file server (hell, not even third place - Though in fairness, I do collect historically-significant Linux distro ISOs).
FWIW, even ripped raw rather than compressed as FLAC, they would still fit on a single 2TB drive. Audio really doesn't present all that much of a problem these days.
Sure, but with the loudness war, they're not really using the 16 bits they have, so what's the point?
Educating people is fine, but the elitists will always say swear that x is better than y, even if it is provably otherwise. Just like some people will swear they saw Elvis working as a hooker at the Rt. 97 truck stop blowing Jesus.
Silence is a state of mime.
I think Truthiness covers half truths too. A half truth is that 24-bit/192kHz audio is higher quality than 24-bit/96KHz audio.
The whole truth is that only your house cat would be annoyed at 96KHz, or an audiophile dog.
That's a profound misrepresentation of how hearing works.
Here's an oversimplified and inaccurate explanation. The ear's mechanism relies on different frequencies providing the highest level of excitation at different places. Your trained nervous system recognizes each different place as a different tone.
For most people, there is no place where sounds above 20 kHz will irritate a nerve ending enough to send an impulse to your brain. Thus, no sound higher than 20 kHz is audible, and 20 kHz corresponds to a 40 kHz sampling rate. (One sample at the low point on the wave, the next sample at the next high point, etc.
Contribute to civilization: ari.aynrand.org/donate
The point is that the 44KHz 16bit track has already been compressed from the original recording. However you rip that track, lossless or lossy, it doesn't matter; you're still not getting the original track.
Actually - it wasn't compressed - it was the limits of the recording equipment at the time. 192KHz/24 bit wasn't common in the 80s.
Knowing this, it doesn't mean that the tracks some sites are selling as 192KHz 24bit are from the original sources, or will even sound better, either. The original track could have been recorded with bad equipment or settings. In other cases, when doing comparisons on CD tracks vs high resolution tracks from sites like HDTracks, you can sometimes find that the HDTracks track is just the CD track with increased reported resolution/file size - possibly due to the inability to acquire the original material, though it could also be as simple as pure greed and laziness. Not that all of the albums on those sites are fakes, but a few of them have been found to be ripoffs.
Unless the track are genuine 192KHz/24 bit tracks, that is true. CD tracks can sound as good or better than 192KHz/24 bit tracks, it all depends upon settings. CD tracks can also sound worse than 92KHz encoded MP3s, again, it depends upon settings.
There's also the fact that it's extremely unlikely anyone can tell the difference between an encode at 96KHz vs 192KHz. If they are both properly encoded from the same source, it's unlikely there will be any audible difference between them.
This, however, is patently false. Given appropriate equipment and a person with a reasonable ear (mine aren't even that great and they suffice) and you can definitely tell the difference between 92KHz and 192Khz, and even straight CD tracks they were encoded from. It does require that the original source have enough depth that something is lost, however. Simple electronica, or other music that samples heavily from trivial sources will not provide enough depth to tell.
At this point my entire collection is lossless (CD quality at a minimum), and yes, it even makes a difference in my car, which has a halfway decent audio system. The other vehicle needs new speakers and an amplifier, the former sound blown and the latter was never clean to begin with, enough so that I pretty much haven't listened to music in it in years, just haven't gotten around to replacing it as it was only short trips anyways.
The cesspool just got a check and balance.
I don't care how highly you think of yourself, until you show me some data you are a worthless troll.
-1 overrated isn't the same thing as "I disagree".
They won't believe you. They believe their ears must be superior to those pseudo-audiophiles. Your post should have ended all discussion, but *sigh* it won't.
Fair point. The people who go on about 24/192 probably don't really listen to the kind of music which is affected by the loudness war. Most audiophiles I know are heavily into jazz or classical music, the recordings of those usually try to be quite faithful to the original.
One thing I know, and that is that I am ignorant...
1. Find post asking for results of a properly conducted double blind test.
2. Ramble on about your various stereo equipment for a couple paragraphs, show a complete ignorance of confirmation bias.
3. Completely fail to provide the requested evidence, wasting every ones time.
4. ???
5. Profit!
-1 overrated isn't the same thing as "I disagree".
Of course this is ludicrous.
No one can see X-rays (or infrared, or ultraviolet, or microwaves). It doesn't matter how much a person believes he can. Retinas simply don't have the sensory hardware.
I wouldn't be so sure... $10 IR filter goggles. The human senses do have limits, but they're rather soft and fuzzy. First, there's genetic variation in the exact sensitivity range (e.g. some people can perceive further into the "infrared" spectrum than others, it's a common high school & college lab experiment). Plus, pedantically, everyone can detect IR up to 3,000 nm at least, cooking would be highly impractical otherwise, and Beethoven felt for vibrations so he could continue composing/performing despite his deafness (IOW, our senses overlap, very important for concert goers that like to feel the bass).
Second, and more importantly, the raw signals are integrated by the brain in a semi-predictable pattern (obviously it's a self-teaching neural network, so people process things differently, although there are common trends). An insect has a compound eye with dozens or hundreds of photoreceptor units. Individually, they're not terribly sensitive, but when integrated provide a much clearer picture. It's akin to how photographers can merge multiple overlapping images to create gigapixel-level quality.
Given harmonics, pinna distortion and such, it wouldn't surprise me if hair cells do not impose an absolute limit on hearing, as the article states. OTOH, I doubt that 192 kHz offers any real sound improvement, but I don't think you can argue that with just biology, as there are few, if any, definites in that subject.
A snare brush rustles at 192/24 instead of sounding like rustling paper.
While that's true, it would definitely also be true at 64/24, and likely at 64/20 I think. While 44/16 is a marginal format that with good D/A conversion can merely deliver what most equipment is able to reproduce, 192/24 is *way* beyond what anyone can hear.
I'm not deaf, but I've never spent more than $10 on headphones.
You'll be in for one heck of a shock the day you hear what music actually sounds like.
There are lots of double blind tests. Most that mean anything are between CD quality and above. No difference found after a year plus of testing. If you want to hear some differences in what's left out when items are compressed A refutation of the validity of double-blind audio tests The main point would be that a well mastered CD is better than a poorly mastered 192kHz/24 bit recording, and the same goes for a poorly mastered CD vs a 192 encoded well mastered piece. However, when the original quality material is of like quality, many can tell the differences until they get to CD quality. After that, a smaller segment can tell. What's been destroying music is the large group of folks who've never heard anything that wasn't put through a pipe filled with a wet sponge first. If that's all you've been exposed to, even the clear trill of a bird might sound unpleasantly harsh in its clarity.
The cesspool just got a check and balance.
Sure, but encoding at lossless (which is what I do for albums that are important to me, rest are 192 kbps iTunes purchases) is entirely different than just wasting space. Lossless has a tangible benefit, whereas as the article points out, outside production, stuff like 24 bit audio does not.
It's the equivalent of encoding beyond lossless, just adding extra bits on top of a lossless encode that you'll never hear ever.
Difficult to explain, but it reminds me of how some people say that there's no point having a frame rate higher than 30 fps. No, your eyes can't actually see the screen flickering above that frame rate, but that doesn't mean it looks perfectly fluid. The author is assuming the point of diminishing returns is actually a point of no returns, which may be far from the truth.
$24 earphones?! You lucky devil.
When I was a wee lad, we had to listen to music through paper cones pressed to our ears. And they weren't real paper, mind you, but a great bloody lot of wasps nests glued together with our own spit.
Youngsters just have no idea.
the trick is getting noise from the real world to sit quietly below the 7 dB loudness that a 16 bit noise floor gives us with an ideal listening environment (ie 83 dB SPL when presented with pink noise at -20dBFS in digital land).
i really hope EBU R-128 gains more momentum. it's been adopted in the broadcast industry very fast, but that's preaching to the choir. i don't think it'll ever make headway in the music industry unless apple rename it "iLevel" and insist on it - rejecting any music submitted to their store that doesn't meet the spec that they totally invented.
If it weren't for the fact that all popular music has its dynamic range compressed to provide maximum loudness for the entire song, dynamic range would be be a problem.
The problem is that, on soft passages, where the high 8 or 10 bits are zero, you're listening to 8 or 6 bit audio. That quantization can be heard. This is a problem for classical recordings made without any dynamic range compression. Of which there are very few.
This is an issue only if you listen to classical music in a very quiet environment. It doesn't matter for car audio. It doesn't matter for Apple's trendy crap earbuds. So almost nobody cares.
no it isn't. verisimilitude is, roughly, the quality of being believably realistic. truthiness is like "verisimilitudinous lying," i.e. the apparent realism is misleading, often toward the exact opposite of the truth.
"They were pure niggers." – Noam Chomsky
There may be no theoretical benefit, but since there's no such thing as an ideal sampler or filter or quantiser, it has many practical benefits.
Here is a quick example. You sample at 44 kHz. The first Nyquist zone is from 0 to 22 kHz, the second one is from 22 to 44 kHz (with flipped spectrum.)
Now, say that some [mechanical] harmonic from some instrument has frequency of 33 kHz. We don't hear those with our ears (parts of the ear are too massive to vibrate fast enough) so no harm done. The orchestra is playing as usual.
But now record this orchestra with an imperfect antialiasing filter (there are reasons why a perfect one wouldn't do you much good anyway.) The 33 kHz harmonic falls into the 2nd Nyquist zone. It will be played back as if it was (22 kHz - 11 kHz = 11 kHz.) Can you hear 11 kHz? Most people hear it just fine. Think about it for a moment. There was no 11 kHz signal in the original spectrum; there was 33 kHz, an inaudible one. The artifact showed up because a [lossy] mathematical operation was performed on the data that describes the signal. The resulting distortion produced an audible tone where none was present originally.
However if you encode at, say, 128 kHz sampling rate, things change. First, the antialiasing filter - even if it is of the same architecture - will have its cutoff way below the Fs/2. This means that signals of the second Nyquist zone will be attenuated by many tens of dB - essentially they can be completely eliminated because nobody cares what you do to ripple and phase above 30 or 40 kHz. Second, for the alias to show up it has to be in LF radio band now, starting at 128 kHz. Microphones aren't even mechanically capable of picking up those frequencies. And finally, if that 33 kHz harmonic passes through the filter (with the same mediocre attenuation as in the first example) ... it will be played back as 33 kHz, and it won't go anywhere. The amplifier will filter it, and the speakers will attenuate it greatly. In other words, a serious distortion that was present when you are sampling at 44 kHz disappears when you are sampling at a much higher rate.
I think I can find a compromise that should work for everyone: Why not just run the needlessly good 24 bit 192 hHz music file though a lossy compressor that does psychoacoustics well - something like AAC or maybe even OGG? Everyone agrees that the vast majority of the data in 24/192 can be thrown away with zero perceptible loss. Fine, let's do it. But let's do the bit discarding in some principled way, guided by a reasonable psychoacoustic model. Isn't that a lot better than indiscriminately downsampling to 16/44.1? By anyone's lights, a 16/44.1 FLAC at 1100 kbps will not sound better than a 24/192 OGG at 1100 kbps - or even 700 kbps, for that matter. The nice thing about this plan is that we have good models for the human threshhold of detection. Scientists claim that 16/44.1 is so good that any improvements on it will not be detected. Maybe, but what if they're wrong? Why not start with the data rich source and apply our acoustic models to throw out only the data that we know is FAR FAR FAR BEYOND our threshhold of detection? It would still be most of it, but at least we'd know we're throwing out the RIGHT data.
Yeah, what would a guy named xiphmont know about signal processing?!
My last hearing test has shown that I can hear up to 21khz. I play Tin Whistle, Great Highland Bagpipe, Ceilidh Pipe, and Guitar. I have heard the rattle of a live sax. I have heard a delicate triangle ringing out over a live orchestra. I have heard live trumpet. I've spent quite a bit of time training my ears to hear those sounds.
.wav .wav .wav and FLAC, encoded with the FLAC reference encoder
I have consistently failed to find a difference between the following in ABX tests I have run:
192/24 and 44/16
96/24 and 44/16
44/16
My reference tracks have been Pink Floyd's "Time", Sirenia's "Meridian", Bach's "Herz und Mund und Tat und Leben" part 7 conducted by Nikolaus Harnoncourt.
The reference system was a PC with an Asus Xonar Essence sound card, a Rogue audio Perseus pre-amp, a pair of Rogue M-180 monoblock power amps, and Vandersteen Signature 2ce speakers. (My father's sound system and my PC).
Of course, msobkow will claim that since I like Highland Bagpipes my hearing is inferior, and I can't hear the differences because he's better than me.
That said, I do like having music in 192/24. Why? Because I can play with it. I can edit it, there's more headroom. If I feel that "Another Brick in the Wall" just needs a tin whistle part, well, I'll have an easier time editing it in without distortion. But for listening? Nope.
Not a sentence!
we're talking about sample rates (kHz). you seem to be talking about bit rates (kbps).
training doesn't make one's senses better. it trains the observer's brain to relay the appropriate signals, rather than ignoring them.
i can spot a boom mic in shot almost subliminally. i can spot jitter of all kinds, motion-compensation artifacts, compression artefacts, spots on film (white and black), and can even tell if a cameraman was running out of film, and when the roll was likely to end by looking at the subtle increase in spottiness. other people can't spot these things.
that said, my eyes are pretty poor. my ears are pretty poor, but i can spot when a (perceptibly) lossy source has been used in a master well before i whip out the spectral view. other people can't.
that said, decent mp3 (lame preset standard, or even medium) flies by undetected. ditto the equivalent transparent settings in all audio encoders. ditto a decent h.264 compared to the film scans it came off, when viewed with the same chroma sampling (otherwise it'd be cheating to compare 4:4:4 with 4:2:0).
my wife can tell you every ingredient that goes into a tiny sample of food. i need twice as large a sample to correctly identify only half as many ingredients. my senses are trained (though not as well), but not as sensitive. good thing considering i work in media production, not food.
my point - you're fooling yourself if you think you have better senses than an average joe - you've just trained you brain to pick different things. they probably enjoy the movie more than you...
On warm summer nights I enjoy sitting on my front porch, with a dry gin made from hand-picked juniper berries, some artisan cheese and bread made out of flour that has been milled before sunrise. And if I am in the mood for it, I also enjoy 192kHz music with my bat friends. For us discerning people this is just a standard of living.
They only determined there's no immediately detectable conscious difference. Now consider this research: http://jn.physiology.org/content/83/6/3548.full So frequencies we don't consciously notice affect brain activity. Thus your reference is not as conclusive as you imply; still need studies to eliminate the possibility that inaudible frequencies do not impact the brain's perception of audible frequencies in a subtle manner over long listening. I've been suggesting we need long-term listening blind tests with psychological assays for about a decade, but haven't found volunteers that want to go through the trouble.
"Politicians and diapers must be changed often, and for the same reason."
44.1 was chosen to fit reasonably well in an NTSC video signal... there's some antique A/D converters out there that output composite and intended to use VHS tapes as media.
48 would have been better, and this was rectified with DVD, but the music industry lags behind...
Blind tests show that we perceive ultrasound: http://jn.physiology.org/content/83/6/3548.full So I suggest you GTFO. Albeit the effect is not conscious, no one has ruled out that it cannot subtly affect the perception of audible sound over long periods of time to the point where a conscious preference may develop in long term listening, without subjects of a study being able to describe the specific difference. In fact, this is more than plausible, given the reference I posted and others like it.
"Politicians and diapers must be changed often, and for the same reason."
Not wanting to go deaf, I use high quality devices with low THD percentages so I can listen at lower volume with maximum impact. Most people don't realize that high volumes are much less necessary as noise is removed and SNR goes up. With a very low noise level, you can play music at relatively low volumes that sounds incredibly good, whereas the high THD injection from a pair of crappy headphones or terrible stereo will cause you to turn up the volume repeatedly to counteract the noise.
- Michael T. Babcock (Yes, I blog)
The ability of the wealthy to afford large hard drives does not mean file sizes aren't an issue for other less fortunate people. My hard drive is 75 GB and most of that is taken with important stuff, as is my external drive, so there's not much room for music and compression matters quite a lot.
I think it's time for you to reacquaint yourself with current disk drive pricing. About six months ago, I got some 2TB drives at about $200 each. The 1TB models were half that and the 500GB even less. And, it you can't retrofit internal SATA drives, they have equivalent [self-powered] USB ones. So, I'm guessing $75 would allow you to upgrade your present system.
Like a good neighbor, fsck is there
I could maybe save you an additional 50%. I have a friend who is also deaf in one ear. You could go halfsies and spend only $12 on a headphone. Which one of your ears works?
No offense, but what was the THD rating on the equipment you used for listening? It really does make a difference. If you listened with a sound card in a PC, you probably lost most of the difference to EM noise.
- Michael T. Babcock (Yes, I blog)
The mighty wiki disagrees: "The reported completion date of the MPEG-1 standard, varies greatly: a largely complete draft standard was produced in September 1990, and from that point on, only minor changes were introduced.[2] The draft standard was publicly available for purchase.[14]"
Analogies don't equal equalities, they are merely somewhat analogous.
Many people think a "factoid" is a small fact. Actually a factoid is something that sounds true, but is actually false.
You were mistaken. Which is odd, since memory shouldn't be a problem for you
Though in fairness, I do collect historically-significant Linux distro ISOs.
Wow, I'm really impressed by that. Do you have the Linux disto that Jefferson wrote the constitution on or the one Hitler used to build the V2 rockets?
Oh come on, everyone knows that Jefferson ran BSD and Hitler insisted on OS/2.
XML is a known as a key material required to create SMD: Software of Mass Destruction
You missed the "soulless" AKA Gingers.
Audiophiles are some of the most amazing people I've ever seen. I've seen some buy $5000 power cords. Yes, that's five thousand dollars.
These guys should be left alone. Just shield any cable with gold and sell them for a couple of thousand bucks, making a 98% margin. That's what they want!
Write boring code, not shiny code!
No professionally conducted double blind test has found any difference above 16/44. None. Even including people that claimed they could tell the difference before the test weren't able to differentiate anything above 16/44. The only ones that claim that are people that have never taken a properly conducted AB double blind testing.
Don't you find it intriguing? It's a bit like telepathy. Some claim they are able to do it. But it has never been proven and boy, have there been a number of tests on this subject! This doesn't prevent some mono zygotic twins to claim they could feel their sibling's accident from 1000km away.
You sound just like them.
Write boring code, not shiny code!
96KHz isn't the audio frequency. It doesn't mean that the audio contains a 90Khz tone. It's the sampling rate. The higher the sampling rate smoother the signal.
Human perception wise a audio signal recorded at 96KHz sampling rate might well be indistinguishable from one sampled at 192Khz, but so is the file size between these files for practical purposes. I don't deceive my self thinking that I'm hearing better sound from a 192Khz file, specially considering that I'm using a basic pair of headphones on a my basic phone to listen to them. But my thinking is that future technologies might let you do interesting things with the extra bit of data which is useless to us right now. So given the choice I opt to get the higher sampled versions. Kind of like with digital pictures which are too noisy or blurred, but which might be cleaned up with future algorithms to give us a slightly more useful picture.
Your comment points out a huge issue with some sites that release high resolution audio, especially if it's older music.
For the last decade, people have been upmixing regular stereo CDs to 5.1, and doing it extremely well. There have been many cases where a few years later the studio releases its own 5.1 version, using the original material (supposedly) and it comes out sounding worse than a stereo upmix that some guy made in his basement. You can search Demonoid for classic examples of this happening, or just to get your hands on some of the upmixes, if you're interested (you'll have to be able to play DTS files).
Back to the point, I wouldn't be surprised if a large amount of the "classic" albums that are released with higher resolutions are just upmixes, which account for situations like HDTracks' Rolling Stones collection being released in multiples of 44. At the very least, it looks like the source material wasn't recorded in the highest quality possible, or maybe at the time the highest possible just wasn't where we are now.
There was already a perfectly good word for that.
Then do some double blind tests that show that you can actually hear the difference.
the guy wants 480khz.
he'd show the difference with a oscilloscope. would be blatantly obvious there. couldn't hear it of course, but you could show a difference when pumping silence!
world was created 5 seconds before this post as it is.
The higher the sampling rate smoother the signal.
Well... no. There's enough information in a low sampled curve. As TFA explains it, the output isn't "jagged" when played back in analog.
Human perception wise a audio signal recorded at 96KHz sampling rate might well be indistinguishable from one sampled at 192Khz
as explained in the article:
- Yup the human ear won't hear anything aboe 20kHz sounds, because it doesn't have any receptors for that.
But there are some real-world problems that come into the mix. No audio installation is perfect. You always get distortions.
- Thus, a 192kHz sampled file could contain frequencies up to 96kHz. These are sound which can't be heard in theory. In practice if you throw 96kHz frequencies to a sub-optimal speaker, the speaker can barf a lot of distortions, including distortion below the the 20kHz. So not only are you trying to output a sound that can be heard, but you force the speaker to produce bad noise *which* is audible.
But my thinking is that future technologies might let you do interesting things with the extra bit of data which is useless to us right now.
Hard to do anything with those bits at all. We simply lack the anatomic feature to do anything with them. Unless you do something like transpose everything at lower frequencie (slow down everything 2x = move everything 1 octave lower). At which point you aren't really outputing the original sound anymore. You're simply using the data to produce new sounds that weren't here to begin with.
The only practical use-case for this would be zoologist studying animals whose sound are beyond the human hear range. In that case "moving everything a couple of octave down" would help the scientist have an approximation with which he can work (to find rythms or other variation that are inaudible in the original frequency range). But that has nothing to do with hearing music made by human, for humans, with instruments designed for human hearing ranges.
Kind of like with digital pictures which are too noisy or blurred, but which might be cleaned up with future algorithms to give us a slightly more useful picture.
The situation with pictures is slightly different. What you're speaking about is spacial frequency. I.e.: resolution.
And human eyes can percieve way much more than some blurry low-res pictures. And in addition to that, there's this thing called zooming which makes perfectly sense to record picture at higher resolution. Because looking at details is simply looking at the same picture at another scale.
The "visual equivalent" to 192kHz sounds would be recording colours outside the human range. Like recording also infra-reds, microwaves, ultraviolets, and X-Rays.
Things that can't never been seen, because human lack the corresponding apparatus. The only way to get someting out of this extra data would be to transpose it into the visible domain. Thus use pseudo-colours to display levels of low infrared (heat), etc.
Just like the "zoologist" use-case above, there are a lot of scientific use-case where that could actually make sense (as an exemple, think about all the data collected by astronomers).
But in no way is it useful to record X-Rays to enjoy a painting by some known artist. The painting was done by a human painter, for human public, using colours chosen for their effect on an un-aided human visual system, disposed on a canvas in a way which is pleasing to the eyes.
(Well, okay. I know that some scientist use infra-red or X-ray image of paintings to analyse how they were done, what are the layers underneath or if there's even another picture over which the current one was painted. But these are scientist analysing the paint, so we're agin on the "scientific analysis" use-case).
24/192 makes sense as an intermediate format to avoid rounding errors, aliasing during filtering, etc.
There could be also some scientific value to keeping
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Don't we already have the word "specious" for things that look true but are not? So might "intentionally specious" be a better definition?
Only if your definition of "perfectly good" is "so convoluted that nobody EVER uses it". ;)
Let's be honest here, verisimilitude exhibits a superlative and ostentatious preponderance of syllables.
"Mind, as manifested by the capacity to make choices, is to some extent present in every electron." -Freeman Dyson
BS. If the overtones of a flute high C and a piccolo high C are both under 22Khz, then sampling at twice that will catch all the overtones, and replaying the sample at the same rate will perfectly reproduce them.
And if the overtones are over 22Khz, but their lower-order harmonics aren't, the sampling will pick up the harmonics and reproduce them perfectly, even without the existence of the original overtone.
There is no subjectivity in that. An oscilliscope will show you that the overtones and/or their harmonics are all there.
The only step that decides whether or not the overtones have any influence is the quality of the low-pass filter. At 44Khz that can be a bit iffy, so using 48Khz to get a little more headroom is nice, but in practice you won't be able to hear a difference with anything above that.
"I know I will be modded down for this": where's the option '-1, Asking for it'?
Comprehension, FTW.
Saying 20KHz is the upper limit of human hearing, is the same as saying that a human may run no faster than 27MPH. You're arguing against something which, obviously, is completely arbitrary.
20KHz is a rule of thumb, not a hard-and-fast limit. I'm glad to hear that you can hear up to 24KHz (and yes, it is an annoying sound), but you simply serve to counter-balance all of the other folks in the world who can't hear a lick past 5KHz (yes, really -- there''s lots of 'em).
(This being Slashdot, I refer you to the MTBF of a hard drive.)
I myself annoyed the hearing-testers at school when I was a kid, because they'd push the "Go" button on the automated tester and I'd keep giving them a thumbs-up for every progressively-higher tone...even though I could hear them telling me the test was finished and I could see that they'd stopped writing. I have no idea how high my hearing used to go. When I finished my own partially-documented tests, I could still hear the tones from the other testing stations from other kids who followed instructions better.
I used to hear 38KHz peizo remote controls, plain as day, though quiet. I was only 7 or 8 at the time.
Can I hear that now? No. Not a chance. I've got a hole around 4KHz, another around 8KHz, and it trails off to nothing lot long after that. The tinnitus takes care of much of the rest, if things are quiet (and if things are loud, it just gets worse in the very long-term).
Too many concerts, too much time listening to angry music, and too much time playing FOH engineer, along with a few hundred thousand miles driving cars seems to me to be an adequate explanation for the loss in my case.
I still listen better than most folks, in that I can interpret what I'm hearing to mean a specific mechanical or electrical issue after decades of careful self-training, but I can't always hear everything that they can.
To this end, I'm in favor of higher sampling rates for recorded music. Why? Because even though I can't hear it anymore, I remember what 38KHz sounds like and if there's any musical information there, some kid will hear it and --hopefully-- enjoy it.
Kid-proof tablet..
You willfully leave out nerds, geeks, dorks, and spazzes? Obvious /. bias! ;)
I8-D
I wish you guys would get this right. There is absolutely no way you can tell the difference between a 15kHz sine wave, square wave, or sawtooth wave (apart from amplitude, perhaps).
Sawtooth waves have even and odd harmonics, and square waves only have odd ones. This means that the first harmonic of a 15kHz sawtooth wave would be at 30kHz, and the square's 3rd harmonic would be at 45kHz. As you pointed out, even if you could hear them, you'd have to have damn good speakers to reproduce.
Three samples is enough to reproduce the 15kHz fundamental per Nyquist.
You're actually wrong. Human ears are relatively good at hearing phase relationships and volume relationships between sounds, as these are key components in determining a sound's direction. Thus, even though you cannot hear the fact that it has turned into a sawtooth wave, you can at least potentially hear that the peak is at the wrong point in time, and you can almost certainly hear that the amplitude is reduced inconsistently from wave to wave.
This paper is also wrong in its claim that 20 kHz is "generous". It isn't. I've done listening tests and have successfully heard high-pitched whines up to... it was either 22 or 23 kHz (which was where I stopped trying, not where I stopped being able to hear), and I'm not even all that young. Admittedly, this is at relatively high amplitude, but the notion that most people can't hear 20 kHz is just plain wrong, and if you start out with that fundamentally wrong premise, you pretty much have to question all the other assumptions, too.
They also make the fundamentally incorrect claim that everything below the nyquist limit is sampled perfectly. This is also provably and trivially false. The Nyquist theorem says no such thing. It merely says that signals above that limit will result in "folding", causing aliased frequencies below the limit, which means that any frequency below the Nyquist limit can be captured without aliasing. However, music is not a single frequency in isolation; it is a bunch of frequencies interacting in complex ways. The Nyquist theorem says nothing about the phase of a signal near the Nyquist limit being consistent relative to other signals at lower frequencies, and in fact, it is not. Nor does the Nyquist theorem state that the frequency will be captured in a way that maintains consistent amplitude as you approach the limit; indeed, it isn't.
Read the Wikipedia article about the Kell factor in display technology, and you'll understand why this is a problem. Notice that with display technology, there is no anti-aliasing filtering involved (because the signal is a known signal that is entirely below the Nyquist limit), so this roughly maps onto what would happen if you could magically create a perfect anti-aliasing filter on the input side. You don't become nearly artifact-free until the frequency you are sampling is about 2/3rds of the Nyquist limit. This is an indisputable fact.
Admittedly, these artifacts are less objectionable in audio because of the anti-aliasing filtering that occurs (both on input and output), but no filter can magically "fix" that inconsistent amplitude. It represents actual information loss—the signal is equally likely to be a constant 15 kHz tone with constant amplitude as it is to be a signal that varies on either side of 15 kHz with a variable amplitude—and once that precise phase and amplitude information is lost, it is impossible to definitively reconstruct it.
In other words, this article is just plain wrong, almost top to bottom.
Besides, the real question is not whether 44.1 kHz is "good enough". It provably isn't, if you care about faithful reproduction over the entire human hearing range. The question is whether the information in the top octave of human hearing is in any way useful or important, to which the answer is "probably not". That's not the same thing as saying that 44.1 kHz or even 48 kHz sampling rate faithfully reproduces the entire range of human hearing, though, but rather it is merely saying that most people don't care about its deficiencies. A 48 kHz sampling rate is "close enough" up to about 16 kHz, which is a broad enough frequency range to be "good enough" for all practical purposes.
Check out my sci-fi/humor trilogy at PatriotsBooks.