Posted by
Hemos
on from the learn-more-about-it dept.
bullitB writes "For fans of the world wide patent conspiracy's latest audio format, the latest double blind AAC encoder comparison test results are in. If nothing else, this suggests much of the complaints regarding the iTunes Music Store's lossyness might be unfounded."
Glad to see development on AAC's sound quality...especially on the free side with the vast improvement of the previously terrible quality of FAAC.
More 'useful' (although it would stir the pot a bit more) would be a comparison with the latest MP3 encoders. To stay within the AAC bubble in comparisons won't encourage people to convert (or to stay away).
Is anybody else in this subthread plagued by associations with the sound of a duck squawking "AFLAC!"?
-- Shop as usual. And avoid panic buying.
Lossy is lossy
by
Anonymous Coward
·
· Score: 5, Interesting
When will people realise that half the trouble with a lossy format is transcoding? Sure, AAC may sound high-quality when it's in its original format, but when you transcode it to MP3 for your MP3 player, the quality turns to shit. This is inevitably the case when dealing with lossy formats, and why I'd rather buy CDs and rip them to FLAC.
Re:Lossy is lossy
by
gl4ss
·
· Score: 4, Insightful
*(Anybody burned them and then ripped them to mp3 from the CD? I can imagine that would be less lossy than straight transcoding.)*
if every device was perfect it would be bitwise identical. and what in the world led you to believe otherwise? if you ran it through analog form in some point you might get 'smoother' sound or something but that's just it and self deceit.
that being said, if you buy music for an mp3 player, buy it in mp3. or rip it yourself from a cd, or just get high enough bitrate it doesn't matter for your golden ears if you code it from one format to another.
better yet buy from some independends that are willing to provide both formats. or fuck, just encode good old amiga mods.
-- world was created 5 seconds before this post as it is.
Re:iTMS music does NOT sound lossy
by
misterpies
·
· Score: 5, Informative
I can tell you're a medical student and not a doctor, because most doctors are much more realistic about the limits of their knowledge. "Scientific" limits on the capabilities of biological systems are often wrong because of some overlooked or unknown factor.
A famous example of this is that for many years scientists could not work out how bees could fly. Their wings were too small, muscles too weak and bodies too heavy. It turned out that bees were able to use previously unknown aerodynamic effects to generate more lift than our previous "knowledge" allowed. Another example is that many birds of prey have visual acuity better than the laws of optics, applied to their eyes, would seem to permit. It turned out that the visual signal processing in their brains is so advanced that birds can actually 'see' features that are below the resolution limit of their eyes.
Similarly, we shouldn't be too dogmatic about what humans can and cannot hear. MP3s (and presumably AACs) compress music by suppressing parts you "can't" hear, not because they're outside your range of hearing but because the brain, assuming those parts should be there, fills in for them even when they're absent.
But it may be that you can't hear something consciously but still tell that it's not there. For example, there was a news story a week or so back showing that people could somehow tell when a picture had changed by the removal of an item in it, even though consciously they could not explain what the difference was - it just 'felt different'.
So, if someone claims to be able to tell the difference between 1 128Kb AAC and a CD, test that claim in a double-blind experiment. Only when he fails the test can you say he was imagining things.
-- The author of this post asserts his moral rights.
I'm not a doctor, but I play one on television
by
AtariAmarok
·
· Score: 4, Informative
It's either that, or "Damn it, Jim, I'm a doctor, not an audiophile!"
It is clear you have no idea what you are talking about. Just because you can't tell the difference does not mean others can.
The people who are "able to tell" just happen to have more sensitive hearing. I'm probably not one of them, but I have known several, including someone who cannot listen to CD's because there is a whine on all of them associated with the digital nature (this same guy does not like going into Radio Shack because of the noise made by their security system.)
Just because you are not a sensitive-eared audiophile does not mean everyone has the same cloth-ears as you do.
-- Don't blame Durga. I voted for Centauri.
Re:I'm not a doctor, but I play one on television
by
Golias
·
· Score: 5, Informative
The parent to this post was modded down for being rude to the grandparent, I suppose... but the point was correct. "The Digital Sound," as we used to call it back in the 80s, turned out to be the result of poor D/A conversion, poor error correction, and amplification hardware that was tweaked to compensate the shortcomings of LPs. Like I mentioned on another audio-related thread last week, a $300 Rotel CD player connected to a modern high-end stereo will sound as good or better when compared to a $3000 air-suspended, laser-guided turntable. (Especially after the LP has been played a few dozen times.)
--
Information wants to be anthropomorphized.
Re:I'm not a doctor, but I play one on television
by
Golias
·
· Score: 5, Insightful
I used to think the same way as your friend, because in the 80s and early 90s there did not seem to be any chance that digital sources could sound as good as my favorite LPs.
Then I heard what good CD players can sound like, and realized that the harshness of CD audio had nothing to do with resolution, and everything to do with component makers cutting corners. Your friend might make the same discovery, if he goes to a good listening room with an open mind.
--
Information wants to be anthropomorphized.
Re:I'm not a doctor, but I play one on television
by
fingerfarm
·
· Score: 4, Interesting
The people who are "able to tell" just happen to have more sensitive hearing. I'm probably not one of them, but I have known several, including someone who cannot listen to CD's because there is a whine on all of them associated with the digital nature (this same guy does not like going into Radio Shack because of the noise made by their security system.)
I'm getting sick of hearing about how Jimmy the cat boy can't listen to CDs, so the rest of the Budweiser crowd has to bow down to his codec choices.
These people are either freaks who feel the need to expound their superiority at any given chance, or audiophiles who feel they're somehow making a difference by making us waste storage space.
At some point you have to choose whether you're listening to the music or the technology used to reproduce it.
Re:iTMS music does NOT sound lossy
by
thatguywhoiam
·
· Score: 4, Funny
FWIW, with the Norah Jones track 'Creepin In' (not used in this test) I can not only ABX every codec bar musepack, I can also spot the aac and mp3 variants because of the way they degrade.
Did you calibrate the flux capacitor?
-- If Jesus wants me it knows where to find me.
Re:AAC is an aberration that should go away
by
DiscoOnTheSide
·
· Score: 4, Informative
AAC is a standard format. Perhaps you've heard of the people that made it... Dolby? Ring a bell? Just about anything doing with excelence in audio comes from them. I can see four things in my shoebox of a dormroom that has their logo on it.
I also find that most of the people that are so violently against DRM (in any form) are the people who would be analy raped by the RIAA/MPAA if they raided your house. I find that the DRM used in the iTunes store is fair, and more or less barely noticeable. Don't have a player that can play AAC? Buy one or shut the fuck up. You bought a player that doesn't do what you want it to, thats no one's fault but your own. Thats like buying DVDs then bitching because your VCR won't play them.
Grow up.
-- Viva La Revolucion! Buy a Mac!
Unfortunately...
by
lotsofno
·
· Score: 5, Informative
Winamp 5.02's encoder (which got a lot of help from hydrogenaudio's own Menno, a FAAD AAC-decoder developer/Ahead MPEG4 developer) wasn't included in the listening test because of a bug they found before testing.
Too bad, too. I would've loved to have seen how it compared.
As a physicist, I'd just like to draw everyone's attention to the error bars on these charts. For the majority of the tests, it's possible to draw a horizontal line through the 95% confidence intervals of nearly all the points.
Hence, the conclusions declaring clear winners/losers in these cases are invalid. If 99% confidence intervals were used (which gives a better statistical test), I feel that no clear winners or losers would be drawn.
Be careful with these sort of studies - even though the author has used confidence intervals, he has failed to use them to infer the proper conclusions.
That said, it's awfully nice to see error bars on this sort of website. Simple data points give such a false sense of precision, I find...
Re:Error bars
by
patman600
·
· Score: 5, Informative
As a high school senior in a Statistics AP class currently studying confidence intervals and hypothesis testing, I think you are missing something. At the beginning, he clearly states your point: "One codec can be said to rated better than another codec with 95% confidence if the bottom of its line segment is at or above the top of the competing codec's line segment." The author gives which one is in first place, but announces at the beginning the requirements for a clear winner. And the author seems to me to be requiring at least half an interval of difference to even say that, much of the time he says they are tied.
Re:Audiophile opinion
by
doofusclam
·
· Score: 4, Insightful
Ha! The audiophiles are nutters, it's true.
But this is different. Bear in mind 'CD quality' ('Red Book' audio) has been established as a base line for the last 10 years or so. Lossy compression degrades this quality by variable amounts depending on what codec is used, what the source material is and at what bitrate it is compressed. The reason for so much development on these codecs isn't to find an audio nirvana, but to minimize the loss from the source material.
Re:Audiophile opinion
by
Amiga+Lover
·
· Score: 5, Insightful
Oh there's definitely a difference in pure analogue vs cd quality vs lossy compression codecs. Just taking a compression ratio down to 96kbit will make most listeners wince when their favourite tracks are played
I think that's part of it for many people. We might not hear parts of the music just like we may not "see" parts of a video clip on the first run round, but after 3 years listening to Louis Armstrong direct from CD, hearing him on 128kbit MP3 can be harsh. Humans learn and learn well, and the repitition of that playing guarantees we'll hear things that we're not meant to! or rather, things that we don't need to in order to identify a particular artist and recording. But we don't just listen to something to identify it, we listen to enjoy. That's different.
Most of the time 128kbit is fine for me. 192kbit for the things I'm familiar with.
As soon as you find someone who starts talking to you about directional audio cables, you must do two things: discount anything else they have ever said to you, and laugh in their faces. While it may seem, to the uninformed, that music 'flows' from the CD / record player out to the speakers, we must always remember that speakers are AC. Alternating current is required to make the speaker cones move in and out.
The real problem is that with all that back and forth motion, the electrons can get very very tired. I recommend that everyone with directional cables should only play their scratchy old LPs for a few minutes each day, lest the electrons in their very expensive cables succumb to extreme fatigue. Come to think of it, the Golden Ear crowd better buy replacements for all their cables once a month -- just in case!
--
Mike van Lammeren It will challenge your head, your brain, and your mind.
Re:iTMS music does NOT sound lossy
by
mhoward736
·
· Score: 5, Insightful
Bollocks! BUT...
If I listen to an MP3 or AAC file on my computer with its sound card and speakers (SB Audigy, Boston Accoustics) I can tell the difference between the same (160kbs) MP3 file and a (128k) AAC - the AAC sounds better. I can't tell the difference between the AAC and a WAV file however.
If I move up to my ($$$$) home stereo then I can easily tell the difference between the compressed and non-compressed versions of the same song. AAC still sounds better to me than MP3 however.
The difference here is money and environment, my office is a noisy place with all the computers etc running. My listening room is quiet and I spent a lot of time setting the stereo up so that its at its best.
I have not looked at OOG or any of the other formats so I can't comment on the relative merits of them.
Re:Audiophile opinion
by
Golias
·
· Score: 4, Interesting
Actually, frequent listening will make your brain better at filling in the data which isn't there. For example: watching DVDs use to bother the heck out of me whenever diffuse lighting created that "layered" effect. Now I hardly ever notice it unless it's ultra-obvious (as with 2001 or some film noir movies), or I'm actively watching for it. My mind usually just interprets it as light fading to darkness now.
The better you know a subject, the more clearly you can "see" it through a dirty window.
P.S. Most of Louis Armstrong's best stuff was recorded on very harsh-sounding "clay 78s." No matter what format you play his Hot Fives and Hot Sevens singles on, it's going to sound like mush. This is another example: People who listen to a lot of live jazz have no trouble listening through all the ticks, pops, scratches, microphone clipping, bad accoustics, etc. and in their "mind's ear" can hear just how brilliant and beautiful Armstrong's recordings are. Those who don't can barely make out a fuzzy-sounding trumpet in an echo-filled hall, and wonder what all the fuss is about.
--
Information wants to be anthropomorphized.
Perspective
by
UnknowingFool
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· Score: 5, Insightful
Not to quash anybody's personal opinion of AAC, there are a few things that we should note.
1) Most people can't tell the difference between formats that are similiar in performance.
2) Some people actually can tell the difference.
3) Some people are just posers who can't tell the difference but say they can.
4) Lastly, most people don't really care as long as it is convenient to use either format.
-- Well, there's spam egg sausage and spam, that's not got much spam in it.
AAC vs. AAC not the issue
by
carbona
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· Score: 4, Interesting
Most of the complaints I've heard registered about the iTunes Music Store 128 Kbps format isn't that it sounds like crap compared to other AAC implementations. The major complaint is that it not only falls far behind Apple's claim that it sounds indistinguishable from the original lossless CD, but it also fails to sound even as good as MP3 with a decent encoder like LAME using --alt-preset standard or OGG at medium quality.
I understand Apple trying to keep filesizes to a minumum, but in these days of 3.0 Mbps DSL links to people's apartments and storage prices at absolutely mind-boggling low price points, their logic is becoming less and less understandable with each passing month.
AAC actually sounds like a well-developed and efficient lossy format but let's up the bitrate a bit especially when the price of a physical CD with all the artwork and liner notes along with lossless tracks and the ability to rip them to a lossy format for portable use is only a few dollars more, and in some cases the same price, than an album on the iTMS.
Sounds good to me
by
kherr
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· Score: 4, Informative
I had all of my CDs ripped to 192kbps MP3. When iTunes came out with AAC, I did a bunch of rip testing. I ripped from Donald Fagen's The Nightfly in a bunch of formats and bitrates. I found, for my personal preference, that 128kbps AAC was at least as good as 192kbps MP3, if not better. So I reripped all of my CDs to 128kbps AAC and got more songs onto my 5GB iPod. Now I'm on to ripping all of my old vinyl to AIFF, eventually to end up as AAC. Huzzah!
Re:Sounds good to me
by
MikeXpop
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· Score: 4, Interesting
I found,
for my personal preference, that 128kbps AAC was at least as good as 192kbps MP3, if not better.
This statement irks me to no end. Your wording is better than most others though as you used for your preference.
The thing to remember is that MP3 and AAC are different encodings. Comparing AAC to MP3 (to OGG to WMA...) is not like comparing MP3 algorithms. AAC will throw out different sounds that MP3 will keep, and vice versa. For example, a symbol crash sounds a lot better on an MP3 than it does on a similarly encoded AAC (I use LAME MP3s and iTunes AACs, they might sound different on others). However, vocals are clearer on AAC than MP3. I find overall AAC is superior to MP3, and that's what I have my songs as. However, saying a 192 AAC == 128 MP3 is a bit faulty. Both have their strengths and both have their weaknesses.
-- Etiquette is etiquette. He kills his mother but he can't wear grey trousers.
Do you ask a car mechanic...
by
SnowDog74
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· Score: 5, Insightful
For the chemical formula for internal combustion? No.
Likewise, I wouldn't go to the local audiophile shop to ask them about audio engineering-related issues.
After being accosted by about ten salespeople in ten minutes at a local audio store that sells everything from Sony ES, to Krell, Wadia, Sunfire and the like... I caught a sales rep in a bold-faced lie.
I was looking for a receiver without many bells and whistles, and he tried steering me towards Denon.
When I asked why Denon is "better", he replied, "Because they focus solely on making audio components unlike Sony."
I chuckled and asked him to explain to me the funadamental difference between the sample & hold buffers on a Sony DAC vs. a Denon DAC... Naturally, he had no clue what I was talking about.
The "double-blind" survey is somewhat misleading... but that being said, it's clearly not measuring which format is superlative... it's only measuring people's perceptions. And people were pretty much even on those various formats.
The study in question just shows that people cannot consistently tell the difference between AAC formats.
Now, I've read articles in audiophile magazines that insisted that SACD (Super Audio CD) was brilliant in comparison to CD. And every one of those articles was a load of crap.
Fundamentally, even the most "discriminating" audiophiles cannot tell the difference between 16-bit, 44.1kHz PCM (Pulse Code Modulation - e.g. AIFF, WAV, in the computer world) and the 1-bit, 2.7GHz DSD bitstream of SACD... nevermind the minute differences betweeen various AAC-enabled codecs.
Hell, I would challenge anyone to be able to tell the difference between 16-bit PCM and MPEG-4 AAC.
The AES (Audio Engineering Society) has stated that MPEG-4 AAC is perceptibly indistinguishable from uncompressed 16-bit, dual channel PCM (e.g. CD-DA spec audio).and I would wager any experienced audio engineer's pair of ears (my own included) against any consumer "audiophile" any day of the week.
My advice to the idle rich? Don't buy the $45,000 pair of speakers... instead buy yourself better hearing and some common sense.
My personal preference? MPEG-4 AAC. As a content creator intensely familiar with a variety of media standards including AES, NTSC, ISO, ITU-R/CCIR, etc. I believe MPEG-4 w/AAC (not Quicktime MPEG-4, mind you, but straight MPEG-4) is the superlative format for compressed audiovisual media.
However, for critical listening, only uncompressed audio is the way to go. The general rule of thumb is that higher bitrates are preferable over higher sampling frequencies. Frequency response roll-off is what you want to avoid. But in order to support the higher bitrates, you need a D/A Converter (DAC, Digital-to-Analog Converter) with an effective sample-hold buffer that can crunch the necessary data to make an accurate conversion of the digital source.
That being said, I'm going to begin digitally remastering my own compositions soon... and go straight from the 24-bit master to a 24-bit multichannel DVD-Audio format. Why? Even an audiophile deafened by the sound of their money burning a hole in their wallet can actually tell the difference between my 24-bit master recordings and the dithered 16-bit CD audio.
Re:You may have a point
by
BorgCopyeditor
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· Score: 5, Informative
They may be pricks (or trolls), but they have some good points. If you can get past the annoying exterior, you might find some good information on these issues by googling for "audiophile" in rec.audio.pro, a group populated primarily by very good recording engineers. These are guys (mostly) who got where they are through both excellent (and aesthetically attuned) hearing and scientific knowledge of how audio works at every point in the signal chain. To watch them dismiss, with unimpeachable arguments and long experience, the claims of "sensitive" audiophiles can be instructive. I speak as one who has been schooled.
-- Shop as usual. And avoid panic buying.
Don't use ANOVA here
by
fscmj
·
· Score: 4, Insightful
In this analysis he presents the results of an ANOVA (Analysis of Variance). This reminds me of the saying: "If your only tool is a hammer, every problem looks like a nail". The tool the author is using is ANOVA and so he is trying to force the data into that form. Hovever, the assumptions of any ANOVA is that the data is independent, normally distributed, and has constant variance. The response ranges from 1.0 to 5.0. I haven't taken the test myself and do not know if users were allowed to select non-integer values or not but even if they were we can see from the graphs he does present that most of the responses were near the upper bound of 5.0. This type of response is clearly not normally distributed. ANOVA is faily resistant to departures from normality but one would need to fully explore the degree of the departure before placing any weight to the confidence intervals presented. My gut feeling here is that it is highly skewed and will present confidence intervals smaller than what they should be (data is forced to be artifically close due to the upper bound and having so many people report values close to that upper bound). The data can probably be viewed as independent but it must be recognized that this is an assumption. Constant variance departures may be a problem as higher responses are less variable than middle responses (due to the upper bound again). It would probably be much better to use a non-parametric test alternative to ANOVA such as a Kruskal-Wallis.
Scope of inference: This is not a random sample from any population and as such cannot be interpreted to represent anything more than the perceptions of the respondants themselves.
-chris
A warning to potential HA posters
by
waaka!
·
· Score: 4, Informative
For good reasons, the posters on Hydrogenaudio don't take kindly to people making unfounded assertions about which codecs are better, so if you're going to argue with them, think twice and ABX first. You will be, after all, arguing with many audio developers, e.g. people who make contributions to LAME, people who've tuned the Vorbis encoder, and a surprising number of people who work for Ahead (makers of Nero, of course).
Slashdot Mirror
You can discuss this test with the author and others at http://www.hydrogenaudio.org
Glad to see development on AAC's sound quality...especially on the free side with the vast improvement of the previously terrible quality of FAAC. More 'useful' (although it would stir the pot a bit more) would be a comparison with the latest MP3 encoders. To stay within the AAC bubble in comparisons won't encourage people to convert (or to stay away).
I am Jack's witty signature line
When will people realise that half the trouble with a lossy format is transcoding? Sure, AAC may sound high-quality when it's in its original format, but when you transcode it to MP3 for your MP3 player, the quality turns to shit. This is inevitably the case when dealing with lossy formats, and why I'd rather buy CDs and rip them to FLAC.
I can tell you're a medical student and not a doctor, because most doctors are much more realistic about the limits of their knowledge. "Scientific" limits on the capabilities of biological systems are often wrong because of some overlooked or unknown factor.
A famous example of this is that for many years scientists could not work out how bees could fly. Their wings were too small, muscles too weak and bodies too heavy. It turned out that bees were able to use previously unknown aerodynamic effects to generate more lift than our previous "knowledge" allowed. Another example is that many birds of prey have visual acuity better than the laws of optics, applied to their eyes, would seem to permit. It turned out that the visual signal processing in their brains is so advanced that birds can actually 'see' features that are below the resolution limit of their eyes.
Similarly, we shouldn't be too dogmatic about what humans can and cannot hear. MP3s (and presumably AACs) compress music by suppressing parts you "can't" hear, not because they're outside your range of hearing but because the brain, assuming those parts should be there, fills in for them even when they're absent.
But it may be that you can't hear something consciously but still tell that it's not there.
For example, there was a news story a week or so back showing that people could somehow tell when a picture had changed by the removal of an item in it, even though consciously they could not explain what the difference was - it just 'felt different'.
So, if someone claims to be able to tell the difference between 1 128Kb AAC and a CD, test that claim in a double-blind experiment. Only when he fails the test can you say he was imagining things.
The author of this post asserts his moral rights.
It's either that, or "Damn it, Jim, I'm a doctor, not an audiophile!"
It is clear you have no idea what you are talking about. Just because you can't tell the difference does not mean others can.
The people who are "able to tell" just happen to have more sensitive hearing. I'm probably not one of them, but I have known several, including someone who cannot listen to CD's because there is a whine on all of them associated with the digital nature (this same guy does not like going into Radio Shack because of the noise made by their security system.)
Just because you are not a sensitive-eared audiophile does not mean everyone has the same cloth-ears as you do.
Don't blame Durga. I voted for Centauri.
Did you calibrate the flux capacitor?
If Jesus wants me it knows where to find me.
AAC is a standard format. Perhaps you've heard of the people that made it... Dolby? Ring a bell? Just about anything doing with excelence in audio comes from them. I can see four things in my shoebox of a dormroom that has their logo on it. I also find that most of the people that are so violently against DRM (in any form) are the people who would be analy raped by the RIAA/MPAA if they raided your house. I find that the DRM used in the iTunes store is fair, and more or less barely noticeable. Don't have a player that can play AAC? Buy one or shut the fuck up. You bought a player that doesn't do what you want it to, thats no one's fault but your own. Thats like buying DVDs then bitching because your VCR won't play them. Grow up.
Viva La Revolucion! Buy a Mac!
Winamp 5.02's encoder (which got a lot of help from hydrogenaudio's own Menno, a FAAD AAC-decoder developer/Ahead MPEG4 developer) wasn't included in the listening test because of a bug they found before testing.
Too bad, too. I would've loved to have seen how it compared.
As a physicist, I'd just like to draw everyone's attention to the error bars on these charts. For the majority of the tests, it's possible to draw a horizontal line through the 95% confidence intervals of nearly all the points.
Hence, the conclusions declaring clear winners/losers in these cases are invalid. If 99% confidence intervals were used (which gives a better statistical test), I feel that no clear winners or losers would be drawn.
Be careful with these sort of studies - even though the author has used confidence intervals, he has failed to use them to infer the proper conclusions.
That said, it's awfully nice to see error bars on this sort of website. Simple data points give such a false sense of precision, I find...
Ha! The audiophiles are nutters, it's true.
But this is different. Bear in mind 'CD quality' ('Red Book' audio) has been established as a base line for the last 10 years or so. Lossy compression degrades this quality by variable amounts depending on what codec is used, what the source material is and at what bitrate it is compressed. The reason for so much development on these codecs isn't to find an audio nirvana, but to minimize the loss from the source material.
Oh there's definitely a difference in pure analogue vs cd quality vs lossy compression codecs. Just taking a compression ratio down to 96kbit will make most listeners wince when their favourite tracks are played
I think that's part of it for many people. We might not hear parts of the music just like we may not "see" parts of a video clip on the first run round, but after 3 years listening to Louis Armstrong direct from CD, hearing him on 128kbit MP3 can be harsh. Humans learn and learn well, and the repitition of that playing guarantees we'll hear things that we're not meant to! or rather, things that we don't need to in order to identify a particular artist and recording. But we don't just listen to something to identify it, we listen to enjoy. That's different.
Most of the time 128kbit is fine for me. 192kbit for the things I'm familiar with.
pay out the nose for single directional cable
Ha ha ha! I love the directional cable talk!
As soon as you find someone who starts talking to you about directional audio cables, you must do two things: discount anything else they have ever said to you, and laugh in their faces. While it may seem, to the uninformed, that music 'flows' from the CD / record player out to the speakers, we must always remember that speakers are AC. Alternating current is required to make the speaker cones move in and out.
The real problem is that with all that back and forth motion, the electrons can get very very tired. I recommend that everyone with directional cables should only play their scratchy old LPs for a few minutes each day, lest the electrons in their very expensive cables succumb to extreme fatigue. Come to think of it, the Golden Ear crowd better buy replacements for all their cables once a month -- just in case!
Mike van Lammeren
It will challenge your head, your brain, and your mind.
Bollocks! BUT...
If I listen to an MP3 or AAC file on my computer with its sound card and speakers (SB Audigy, Boston Accoustics) I can tell the difference between the same (160kbs) MP3 file and a (128k) AAC - the AAC sounds better. I can't tell the difference between the AAC and a WAV file however.
If I move up to my ($$$$) home stereo then I can easily tell the difference between the compressed and non-compressed versions of the same song. AAC still sounds better to me than MP3 however.
The difference here is money and environment, my office is a noisy place with all the computers etc running. My listening room is quiet and I spent a lot of time setting the stereo up so that its at its best.
I have not looked at OOG or any of the other formats so I can't comment on the relative merits of them.
The better you know a subject, the more clearly you can "see" it through a dirty window.
P.S. Most of Louis Armstrong's best stuff was recorded on very harsh-sounding "clay 78s." No matter what format you play his Hot Fives and Hot Sevens singles on, it's going to sound like mush. This is another example: People who listen to a lot of live jazz have no trouble listening through all the ticks, pops, scratches, microphone clipping, bad accoustics, etc. and in their "mind's ear" can hear just how brilliant and beautiful Armstrong's recordings are. Those who don't can barely make out a fuzzy-sounding trumpet in an echo-filled hall, and wonder what all the fuss is about.
Information wants to be anthropomorphized.
1) Most people can't tell the difference between formats that are similiar in performance.
2) Some people actually can tell the difference.
3) Some people are just posers who can't tell the difference but say they can.
4) Lastly, most people don't really care as long as it is convenient to use either format.
Well, there's spam egg sausage and spam, that's not got much spam in it.
Most of the complaints I've heard registered about the iTunes Music Store 128 Kbps format isn't that it sounds like crap compared to other AAC implementations. The major complaint is that it not only falls far behind Apple's claim that it sounds indistinguishable from the original lossless CD, but it also fails to sound even as good as MP3 with a decent encoder like LAME using --alt-preset standard or OGG at medium quality.
I understand Apple trying to keep filesizes to a minumum, but in these days of 3.0 Mbps DSL links to people's apartments and storage prices at absolutely mind-boggling low price points, their logic is becoming less and less understandable with each passing month.
AAC actually sounds like a well-developed and efficient lossy format but let's up the bitrate a bit especially when the price of a physical CD with all the artwork and liner notes along with lossless tracks and the ability to rip them to a lossy format for portable use is only a few dollars more, and in some cases the same price, than an album on the iTMS.
I had all of my CDs ripped to 192kbps MP3. When iTunes came out with AAC, I did a bunch of rip testing. I ripped from Donald Fagen's The Nightfly in a bunch of formats and bitrates. I found, for my personal preference, that 128kbps AAC was at least as good as 192kbps MP3, if not better. So I reripped all of my CDs to 128kbps AAC and got more songs onto my 5GB iPod. Now I'm on to ripping all of my old vinyl to AIFF, eventually to end up as AAC. Huzzah!
For the chemical formula for internal combustion? No. Likewise, I wouldn't go to the local audiophile shop to ask them about audio engineering-related issues. After being accosted by about ten salespeople in ten minutes at a local audio store that sells everything from Sony ES, to Krell, Wadia, Sunfire and the like... I caught a sales rep in a bold-faced lie. I was looking for a receiver without many bells and whistles, and he tried steering me towards Denon. When I asked why Denon is "better", he replied, "Because they focus solely on making audio components unlike Sony." I chuckled and asked him to explain to me the funadamental difference between the sample & hold buffers on a Sony DAC vs. a Denon DAC... Naturally, he had no clue what I was talking about. The "double-blind" survey is somewhat misleading... but that being said, it's clearly not measuring which format is superlative... it's only measuring people's perceptions. And people were pretty much even on those various formats. The study in question just shows that people cannot consistently tell the difference between AAC formats. Now, I've read articles in audiophile magazines that insisted that SACD (Super Audio CD) was brilliant in comparison to CD. And every one of those articles was a load of crap. Fundamentally, even the most "discriminating" audiophiles cannot tell the difference between 16-bit, 44.1kHz PCM (Pulse Code Modulation - e.g. AIFF, WAV, in the computer world) and the 1-bit, 2.7GHz DSD bitstream of SACD... nevermind the minute differences betweeen various AAC-enabled codecs. Hell, I would challenge anyone to be able to tell the difference between 16-bit PCM and MPEG-4 AAC. The AES (Audio Engineering Society) has stated that MPEG-4 AAC is perceptibly indistinguishable from uncompressed 16-bit, dual channel PCM (e.g. CD-DA spec audio).and I would wager any experienced audio engineer's pair of ears (my own included) against any consumer "audiophile" any day of the week. My advice to the idle rich? Don't buy the $45,000 pair of speakers... instead buy yourself better hearing and some common sense. My personal preference? MPEG-4 AAC. As a content creator intensely familiar with a variety of media standards including AES, NTSC, ISO, ITU-R/CCIR, etc. I believe MPEG-4 w/AAC (not Quicktime MPEG-4, mind you, but straight MPEG-4) is the superlative format for compressed audiovisual media. However, for critical listening, only uncompressed audio is the way to go. The general rule of thumb is that higher bitrates are preferable over higher sampling frequencies. Frequency response roll-off is what you want to avoid. But in order to support the higher bitrates, you need a D/A Converter (DAC, Digital-to-Analog Converter) with an effective sample-hold buffer that can crunch the necessary data to make an accurate conversion of the digital source. That being said, I'm going to begin digitally remastering my own compositions soon... and go straight from the 24-bit master to a 24-bit multichannel DVD-Audio format. Why? Even an audiophile deafened by the sound of their money burning a hole in their wallet can actually tell the difference between my 24-bit master recordings and the dithered 16-bit CD audio.
They may be pricks (or trolls), but they have some good points. If you can get past the annoying exterior, you might find some good information on these issues by googling for "audiophile" in rec.audio.pro, a group populated primarily by very good recording engineers. These are guys (mostly) who got where they are through both excellent (and aesthetically attuned) hearing and scientific knowledge of how audio works at every point in the signal chain. To watch them dismiss, with unimpeachable arguments and long experience, the claims of "sensitive" audiophiles can be instructive. I speak as one who has been schooled.
Shop as usual. And avoid panic buying.
In this analysis he presents the results of an ANOVA (Analysis of Variance). This reminds me of the saying: "If your only tool is a hammer, every problem looks like a nail". The tool the author is using is ANOVA and so he is trying to force the data into that form. Hovever, the assumptions of any ANOVA is that the data is independent, normally distributed, and has constant variance. The response ranges from 1.0 to 5.0. I haven't taken the test myself and do not know if users were allowed to select non-integer values or not but even if they were we can see from the graphs he does present that most of the responses were near the upper bound of 5.0. This type of response is clearly not normally distributed. ANOVA is faily resistant to departures from normality but one would need to fully explore the degree of the departure before placing any weight to the confidence intervals presented. My gut feeling here is that it is highly skewed and will present confidence intervals smaller than what they should be (data is forced to be artifically close due to the upper bound and having so many people report values close to that upper bound). The data can probably be viewed as independent but it must be recognized that this is an assumption. Constant variance departures may be a problem as higher responses are less variable than middle responses (due to the upper bound again). It would probably be much better to use a non-parametric test alternative to ANOVA such as a Kruskal-Wallis. Scope of inference: This is not a random sample from any population and as such cannot be interpreted to represent anything more than the perceptions of the respondants themselves. -chris
For good reasons, the posters on Hydrogenaudio don't take kindly to people making unfounded assertions about which codecs are better, so if you're going to argue with them, think twice and ABX first. You will be, after all, arguing with many audio developers, e.g. people who make contributions to LAME, people who've tuned the Vorbis encoder, and a surprising number of people who work for Ahead (makers of Nero, of course).