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Public AAC Listening Test @ ~96 Kbps [July 2011]. 277

Posted by timothy from the listening-for-artifacts dept.
The folks at the Hydrogen Audio Forums have for years been benefiting the world with their patience, technical skills, and hyper-focus on sound quality, by comparing the real-world sound of various codecs and bit-rates for audio encoding. Under the scope for the latest public listening test (slated to run until July 27) are the following AAC encoders: Nero 1.5.4; Apple QuickTime 7.6.9 true VBR; Apple QuickTime 7.6.9 constrained VBR; Fraunhofer (Winamp 5.62); Coding Technologies (Winamp 5.61); and ffmpeg's AAC (low anchor).
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Public AAC Listening Test @ ~96 Kbps [July 2011]. More

Public AAC Listening Test @ ~96 Kbps [July 2011].

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  • Comment removed (Score:5, Funny)

    by account_deleted ( 4530225 ) on Sunday July 24, 2011 @06:01PM (#36865840)
    Comment removed based on user account deletion

  • So some people will say Codec A sounds best. Some will say Codec B sounds best. Some will say that Codecs A and B suck donkey shit and Codec C sounds best. What exactly does this prove?

    • Well, maybe if enough people do that and a clear winner emerges, that would prove something? Or don't you believe in statistical effects?
    • For you, probably nothing. But some people have inquiring minds. They are the reason we don't all live in caves banging rocks together.

    • Re:And the point of this is? (Score:5, Informative)

      by GrievousMistake ( 880829 ) on Sunday July 24, 2011 @07:03PM (#36866254)

      The Hydrogen Audio Forums tests have traditionally used a sound methodology, it would probably be worth reading up on it [hydrogenaudio.org] before you comment, lest you make a fool out of yourself.

      They will not be trying to measure how 'good' each codec sounds, they are trying to measure how close it is to the source material, with a 'perfect score' being statistically indistinguishable.

    • maybe the point isn't to prove anything but provide a common reference point and place to discuss these encoders.

      so.. those who prefer codec A go that way,
      those who prefer codec B use that one, and
      those who have an affinity for donkey shit go with C.

      this isn't called the Hydorgen Audio Contest, it's called the Hydrogen Audio Test..

      what is the objective of running tests? gethering data.

    • So some people will say Codec A sounds best. Some will say Codec B sounds best. Some will say that Codecs A and B suck donkey shit and Codec C sounds best. What exactly does this prove?

      That people who think an inferior codec sounds better have no judgment?

    • Re: (Score:2)

      by mysidia ( 191772 ) *

      So some people will say Codec A sounds best. Some will say Codec B sounds best. Some will say that Codecs A and B suck donkey shit and Codec C sounds best. What exactly does this prove?

      It can show what percentage of the population on average could be expected to favor Codec A for a certain sample.

      As for generalizing how Codec A/B/C did over one sample to the overall perceptions of Codec A/B/C over all possible samples a simple listening test cannot do that.

      Making any kind of general statement abou

    • That's precisely because of the placebo effect. Something that an A/B/X test eliminates ;)

  • FLAC (Score:3, Interesting)

    by ThePhilips ( 752041 ) on Sunday July 24, 2011 @06:19PM (#36865968) Homepage Journal

    I'm staying mostly with FLACs. Works for me. The difference between AAC/MP3 and FLAC (and CD player *) my hi-fi allows to hear quite clearly.

    (*) Source for AAC/MP3/FLAC is the Squeezebox Touch (via DacMagic) and when compared to the CD player, the difference of sound quality is noticeable. Not out right bad (that would be Squeezebox w/o DacMagic), in fact quite OK, but still far from the proper hi-fi CD player.

    • Re:FLAC (Score:5, Insightful)

      by maeka ( 518272 ) on Sunday July 24, 2011 @06:27PM (#36866012) Journal

      The difference between AAC/MP3 and FLAC (and CD player *) my hi-fi allows to hear quite clearly.

      If you really can easily distinguish well-encoded AAC or MP3 from FLAC you should lend us at HA your golden ears!

      I rather strongly suspect once subjected to rigorous double-blinding you might not come back speaking so boldly.

      • If you really can easily distinguish well-encoded AAC or MP3 from FLAC you should lend us at HA your golden ears!

        FLAC sound clearer to me. Even when compared to AAC @ 192kbps or MP3 @ 320kbps. AAC or Vorbis @ 192kbps is how I archived my music before I had hi-fi - now it is FLAC. Some of my friends use MP3 @ 320kbps. And yes, I hear the difference on both jazz and classics. More on the former - less on the latter, unless this is a piano/pianissimo piece. Quiet parts suffer most from lossy compression.

        Yes, I have absolute pitch, if that plays any role. In past I have tuned guitars though never learned to play them.

        • Re:FLAC (Score:5, Informative)

          by maeka ( 518272 ) on Sunday July 24, 2011 @07:03PM (#36866248) Journal

          FLAC sound clearer to me.

          That is not a description of the type of artifact one is likely to find in AAC or MP3. Try again.

          Yes, I have absolute pitch, if that plays any role.

          Nope, that isn't where lossy codecs fail either.

          I do not understand why people get up in arms when somebody says they her the difference: be glad that you do not.

          Up in arms? No. It was an honest inquiry. If you are truly able to distinguish AAC/MP3 from FLAC on a general basis you would be most valuable.

          Ya see, lossy codecs tend to fail in particular ways on specific types of samples. If someone was able to readily distinguish lossless from lossy across a wide (or even moderate) collection of samples they would be damn near unique and quite useful as a tester of dev changes.

          Alas lots of people talk and few actually prove they're swinging the big dick they brag about once subjected to double-blind testing.

          • I wish you luck.

            In my experience, almost nobody in the "I can hear the difference between Mp3 at 320kbps and source" people will ever EVER get around to doing an ABX test.

            In fact, I can only remember one... and amazingly enough, that guy actually was able to produce something like a 13/16 test result on 320kbps mp3 he made himself using the latest release of LAME. of course that was only on one sample, and when I asked him to explain what differences he heard between the mp3 and the source, he couldn't.

          • I'm not sure, but I may be one of those people. How do I go about doing a double-blind test?

            In general, I can easily distinguish 160 kbps MP3 or 96 kbps AAC from a lossless encoding, sometimes to the point where it distracts from the enjoyment of what I'm listening to. I consider well encoded 192 kbps MP3 or 128 kbps AAC a minimum for something to sound "good" (not "great"). At this rate I'll often hear minor distortions, but they're generally small enough to ignore and not distracting if I'm focused on dri

        • Re: (Score:2)

          by nzac ( 1822298 )

          Some of my friends use MP3 @ 320kbps. And yes, I hear the difference on both jazz and classics.

          You need to sound like a much bigger dick to come up with something creditable. You would have to authenticate that you friends actually knew what they were doing when the rips were made are the latest lame ripped with EAC with at lest the -h option and maybe some other stuff or was it some shitty program that ripped as fast as possible 8 years ago (i got some terrible rips from lame due to trusting a flacon last month). Its not a remotely blind test and 'clearer' is a very subjective term for some music. M

        • i think the fact that you can distinguish between two codecs does not imply that you can judge which is better in a blind test. sometimes inferior codes do sound better.

      • Indeed, I rip to FLAC mainly for a back up, but I tend to listen to 196kbps VBR MP3s most of the time because I can't hear the difference. Well, when I'm not on the computer with my backups.

      • Do you have a handy test available? I imagine a simple set of say 4 pages, which has 2 WAV or FLAC files, and you have to listen and decide which is the original and which is the encoded/decoded one. After 4 you have 75% accuracy. So an initial self test should be easy to set up, you just need to randomize the filenames and whether the uncompressed one is on the right or left.

        I've always had problems with MP3, mostly the bass drum in pop rock (usually a drum machine, not a real drum set). It sounds thin

      • Re: (Score:2)

        by mysidia ( 191772 ) *

        If you really can easily distinguish well-encoded AAC or MP3 from FLAC you should lend us at HA your golden ears!

        Not necessarily. The ability to hear a difference depends partly on the type and quality of your sound system.

        By the way, I prefer and use Apple Lossless 94khz/24-bit (.M4A) over FLAC. Not that FLAC sounds any different; I just find that working with the files seems faster, as in compressing raw audio to M4A seems to happen at a much better rate than compressing the same data to FL

    • Many claim so and most a quite wrong. (Score:5, Informative)

      by guidryp ( 702488 ) on Sunday July 24, 2011 @06:52PM (#36866170)

      Almost no one can hear a difference between loss-less and any of the codecs at high bit rates (256K+).

      Though many think they can, until actually blind tested.

      If you can reliably tell the difference in proper blind testing, you are likely have better hearing/perception than 99.9999 % of the population.

      I think I have great hearing, but when I did some ABX testing, my ability to distinguish drops off completely by 160 K VBR on MP3s and that is in quiet room with quality headphones straining to ID any difference.

      I am skeptical of any golden eared claims these days pooh-poohing modern codecs.

      • You're right, I can't tell the difference between a CD-ripped FLAC and a high-quality MP3/Vorbis/AAC at high bit-rate encoded from the same source. However, why would I bother with losing any information at all? If I keep the FLACs and CUE sheet, I have an exact duplicate of the original disc, for maybe twice the storage of a high-quality lossy file. I also use fewer resources decoding that audio. I also have the benefit of Vorbis-style comments.

        Hard drives are available at 3TB for wouldn't choose a lossles

        • originally the argument was battery life on portables mostly, although I don't know that it matters nearly as much in the age of large flash-based storage. It mattered a few years ago because the only players large enough to store more than two dozen FLACs had hard drives, not flash storage.

          But on a home pc? I agree that there is no reason not to use FLACs, if only for future transcoding purposes.

          • I have a 5th-gen iPod Video, with a spinning hard drive. I installed Rockbox on it so that I wouldn't have to encode my FLACs. In the beginning, battery life was horrible, until they figured out how to use the on-board hardware MP3 decoder. Then battery life was pretty comparable between running Rockbox or the stock firmware. FLAC files, however, have always been better on battery life than either of the other two. The efficiency gains in the CPU must have outweighed the added hard drive access.

            Aikon-

            • last time I tested, I got about 2 hours better on mp3 than I did on vorbis, specifically because vorbis couldn't use the internal mp3 decoder hardware... so if they figured out how to get FLAC to use that, it doesn't surprise me that it gets good battery life now. That said, they must buffer a lot of flac, because it used to spin up and spin down the HD a whole lot (thus the source of the bad battery life hit with flac, as it needed to spin up and spin down more often).

              • Re: (Score:2)

                by maeka ( 518272 )

                There is no internal MP3 decoder. It's a dual-core ARM processor. Period.

                MP3 is more efficient than vorbis on the PortaPlayer targets because we use both cores in decoding.

                Stop talking about this nonexistant mp3 decoder hardware. Since the original Archos players 99.9% of MP3 players have been software decoders on generic CPUs.

                • The last time I read on the subject, which admittedly was a couple years, rockbox's own wiki refered to ipods as having custom mp3 decoding hardware.

                  I can't be blamed for being misinformed from the source.

                • 99.9 %? Perhaps true of dedicated music only devices, but these days there are many other devices that play audio and which are making dedicated audio players redundant for many people. Phones and tablets tend to use DSP hardware decoding instead of software decoding. This is the case for my clunky old Nokia devices (2730 phone and N810 tablet) and for my new Archos A43IT tablet. A quick google and visit to wikipedia shows that both the iPods and iPod Touch use hardware decoders - Sigmatel, Wolfson and

              • Re: (Score:2)

                by aevan ( 903814 )
                Personally have a cheap little 4Gig Flash Clip+ for running/blading (logic is "if I'm falling I don't want to be distracted with worry about damaging my player".

                A full charge lasted somewhere between one and two hours playing FLAC, catching me by surprise. Re-encoding with 192 cbr shot that to ten-ish.

                </personal anecdote>

      • Re: (Score:3, Informative)

        by ThePhilips ( 752041 )

        Though many think they can, until actually blind tested.

        I listen mostly classics and jazz. MP3@320kbps sounds different from the FLAC. More I can't tell you. Test wasn't scientific and only partially blind: I accidentally picked from my friend's library a copy of my own CD in MP3 and played it. It sounded differently to what used to hear. Upon checking I found that those were not my FLACs, but my friend's MP3s instead.

        But yeah, I will likely fail at a proper blind test: it is simply extremely tiring to listen to all the samples and maintain a concentration f

        • Re: (Score:2)

          by guidryp ( 702488 )

          Though many think they can, until actually blind tested.

          I listen mostly classics and jazz. MP3@320kbps sounds different from the FLAC. More I can't tell you. Test wasn't scientific and only partially blind: I accidentally picked from my friend's library a copy of my own CD in MP3 and played it. It sounded differently to what used to hear. Upon checking I found that those were not my FLACs, but my friend's MP3s instead.

          Chances are your friend messed up the encode or disc ripping. I have heard a great many terrible MP3 encodes from friends/net etc... I am not sure how some people mess them up, but they do.

          Any encodes I have done myself have never had these problems.

          • I concur. on normal music (i.e. non-"known problem samples"), I have problems ABXing LAME even at VBR ~128kbps (v6 i think?) nowadays.

      • Re: (Score:2)

        by godrik ( 1287354 )

        I agree with you. I definitely can not hear the difference between flac and badly encoded MP3. Still I keep on using FLAC. Because the space difference between highly encoded mp3 and FLAC is not so significant. When I will have to reencode for some reason, I might start hearing the difference. Lately, I needed to encode for a portable player which did not have so much memory. Coming from FLAC allows me to reencode the original soundtrack. So I do not accumulate imprecision. I always have a high quality sour

        • Re: (Score:2)

          by adolf ( 21054 )

          I use high-bitrate MP3 so that I never, ever have to re-encode anything to begin with: It quite simply already plays everywhere, on every bit of audio kit that I have, from my cars to my living room to the various widgets I carry in my pocket. FLAC, on the other hand, only plays natively on my PC(s) and my Android phone, and is something I'd need to convert to some other format in order to use.

          It's not about space, as storage is plentiful and cheap. And it's not about quality, as LAME @320kbps is quite a

        • Re: (Score:2)

          by guidryp ( 702488 )

          Someone beat me to it, but it is already in high quality MP3, that sounds perfectly equivalent to me (I did ABX testing) and plays everywhere. I have no need to re-encode because size is already small and again it plays everywhere.

          I have no problem if you want Flacs for whatever reason if you are trying to preserve your original disks or something, but there really is no sonic reason not to use MP3.

      • Re: (Score:3, Interesting)

        by evilviper ( 135110 )

        If you can reliably tell the difference in proper blind testing, you are likely have better hearing/perception than 99.9999 % of the population.

        This is not true.

        Frequency-domain codecs have known artifacts that CANNOT be eliminated. Pre-echo is probably the best-known example. A sample with heavy percussion or other complex impulses (like audience applause) will stand out like a sore thumb... Audience applause is one of the standards dating back to the 70s when human audio perception / lossy audio compre

        • This is not true.

          Frequency-domain codecs have known artifacts that CANNOT be eliminated. Pre-echo is probably the best-known example. A sample with heavy percussion or other complex impulses (like audience applause) will stand out like a sore thumb...

          Have you tried the test or is are you relying on something you read?

          I just downloaded the files mentioned in the main post. There are 20 samples I gave them a quick run through inside ABC-HR.

          The low mark (I assume) stands out like a sore thumb.

          But for the other 5 samples, the seem quite indistinguishable on a casual listen.

          There is one sample with a sharp percussive instrument (castenatas?) and really I can't spot the difference.

          And these are 96K files!!

          The state of the art is improving all the time.

          • We're talking about a field of science, here. I've never tried to send 100 amps down a phone line, but I know damn-well exactly what would happen.

            "I can't hear it" isn't an argument. It's an extremely subjective individual observation which cannot be challenged or refuted.

            "96K is far below the threshold of Perceptual Entropy", however, is a pretty well irrefutable argument, based on the relevant scientific theories.

            My previous statement, that frequency-domain codecs can never produce transparent audio, is

            • It doesn't matter if it is transparent to a machine. You are simply going by something you read as opposed to actually testing how well it works in practice.

              If you want to toss around cute quotes, here is one for you:
              "In theory, practice and theory are the same. In practice, they are not."

              • It doesn't matter if it is transparent to a machine.

                No it doesn't. That's why we're talking about human perception. You obviously don't have a clue what "Perceptual Entropy" is, even though I suggested you look it up, and mentioned it multiple times now. I don't know what there is to debate when you don't even understand the words I'm typing.

                You are simply going by something you read as opposed to actually testing how well it works in practice.

                I'm going on 4 decades of the top scientific papers in the fi

            • Re: (Score:2)

              by Pieroxy ( 222434 )

              What are you talking about? There are tests out there that virtually no one are able to ABX. These are the tests we are talking about. What are YOU talking about?

              "I can't hear it" isn't an argument.

              But if nobody can hear it, does that make it inaudible?

            • Re: (Score:3)

              by fbjon ( 692006 )

              "I can't hear it" isn't an argument. It's an extremely subjective individual observation which cannot be challenged or refuted.

              If nobody can hear it, then I'd say it is an argument. This is perception we're dealing with, after all, so subjectivity in the test subjects is rather to be expected, no?

              My previous statement, that frequency-domain codecs can never produce transparent audio,

              I'm not sure what you mean by this. A codec operating at what bitrate?

              If I make a codec that simply transforms between domains (hence using the same bitrate as the original signal), it's going to be transparent. Surely you're not claiming that by e.g throwing away only one bit from the entire signal, it will suddenly become non-transparent

  • FFmpeg's AAC encoder is not finished (Score:4, Informative)

    by Cigaes ( 714444 ) on Sunday July 24, 2011 @06:21PM (#36865976) Homepage

    FFmpeg's AAC encoder is not finished (yet?), and flagged as experimental. Including it in such a test is rather a dubious idea: it is likely to give a bad impression of the whole project.

    Having the new vo-aacenc [sourceforge.net] as contender for the Free Software community would IMHO have been more relevant.

    • Re: (Score:2)

      by Shrubbman ( 3807 )

      FFmpeg's AAC encoder is not finished (yet?), and flagged as experimental. Including it in such a test is rather a dubious idea: it is likely to give a bad impression of the whole project.

      Having the new vo-aacenc [sourceforge.net] as contender for the Free Software community would IMHO have been more relevant.

      Well they ARE using it as the low anchor, i.e. they know full well it's gonna sound bad so if people wind up rating it higher than any of the other options that's an indication that something odd and/or wrong has happened, plus it's helpful just to see a worst case scenario option on the list.

    • Re: (Score:2)

      by guruevi ( 827432 )

      I think the FFmpeg encoder is more widely used however even for AAC. It is bundled (or a dependency) in a lot of open source software.

    • FFmpeg is made of developers, not PR hounds. They're going to care more about data---seeing how close they are in quality---than random people deciding FFmpeg sucks.

  • What's the point? (Score:3)

    by ronocdh ( 906309 ) on Sunday July 24, 2011 @06:21PM (#36865978)
    I'm no audiophile, though I do take the time (and space) to rip everything I buy to FLAC. What's the intended application of encoding around 96kbps? Most audio streams online passed that mark many years ago. All in all, this seems like a question best answered years ago. Can anyone point me to what I'm missing here?

    • Re: (Score:2)

      by rts008 ( 812749 )

      I think that is referring to the sampling rate it was recorded at, not the playback bit rate of the recording.

    • Re: (Score:2, Informative)

      by progkeys ( 253222 )

      Have you ever done game programming? Here's one example: multimedia iOs apps, like games and enhanced books are severely memory constrained. Every kB saved can make a difference. Even in a large console game, memory becomes an issue. Most AAA games have hours of prerecorded music, sound effects and voiceover. If console developers can squeeze their audio by an extra 5%, without degrading the audio too much, that makes a big difference to the the memory footprint (or the amount of audio). I do audio a

  • Subjective audio comparisons are useless (Score:3)

    by HonkyLips ( 654494 ) on Sunday July 24, 2011 @06:52PM (#36866178)

    It is impossible to judge audio codecs through subjective tests.
    Companies that manufacture loudspeakers have spent hundreds of millions of dollars on audio quality research- not in order to make their speakers better, but to understand the psychology behind the sounds that make people choose speaker A over speaker B in a showroom. They have discovered all sorts of quirks in human psychology and perception that they exploit to boost their sales, and they have little to do with overall 'quality'. Decades of expensive, meticulous, scientifically valid studies are responsible for the range of speakers you find at the average hifi shop, and even when several identical speakers are demonstrated (but the listener is told they are all different) most people will say that speaker number 2 sounds the best.
    The same applies to audio codecs. Even if you eliminate all sorts of hardware variables, then just listening to clip A, then B, then C and subjectively deciding which one sounds 'best' is totally unreliable. The results of this type of testing are completely useless. At the very least you would need to set up a triangle test, and to do this properly with 6 codecs in a controlled environment would take a very long time and the results still wouldn't correlate with true 'quality' unless it was repeated many times with different hardware setups.
    Ignoring the psychological weaknesses in these types of tests, the playback hardware would colour the sound enough as to make the underlying test - the codec - invalid. The choice of music, the amplifier, the speakers or headphones, and the volume used for playback will all contribute their own distinctive characteristics to the audio so that person A will not be hearing the same test as person B.
    Forget codec wars. Just buy a decent pair of earphones.

    • The point is that if they're that close then it doesn't really matter. One can then choose the codec that delivers the desired quality in the fewest bits or possibly that costs the least amount of money.

    • It is impossible to judge audio codecs through subjective tests. Companies that manufacture loudspeakers have spent hundreds of millions of dollars on audio quality research- not in order to make their speakers better, but to understand the psychology behind the sounds that make people choose speaker A over speaker B in a showroom. They have discovered all sorts of quirks in human psychology and perception that they exploit to boost their sales, and they have little to do with overall 'quality'. Decades of expensive, meticulous, scientifically valid studies are responsible for the range of speakers you find at the average hifi shop, and even when several identical speakers are demonstrated (but the listener is told they are all different) most people will say that speaker number 2 sounds the best. The same applies to audio codecs. Even if you eliminate all sorts of hardware variables, then just listening to clip A, then B, then C and subjectively deciding which one sounds 'best' is totally unreliable. The results of this type of testing are completely useless. At the very least you would need to set up a triangle test, and to do this properly with 6 codecs in a controlled environment would take a very long time and the results still wouldn't correlate with true 'quality' unless it was repeated many times with different hardware setups. Ignoring the psychological weaknesses in these types of tests, the playback hardware would colour the sound enough as to make the underlying test - the codec - invalid. The choice of music, the amplifier, the speakers or headphones, and the volume used for playback will all contribute their own distinctive characteristics to the audio so that person A will not be hearing the same test as person B. Forget codec wars. Just buy a decent pair of earphones.

      You're completely missing the point. This test is a comparison between the lossless reference samples and the codecs. You have 3 Play buttons. One is the reference file (and it TELLS you it's the reference file), the other two are randomly assigned to be the identical reference file or the lossy encode and it DOESN'T tell you which. You are supposed to choose which one is the encode and how poor it sounds compared to the reference. It's an objective test that has nothing to do with your hardware because you

      • You are supposed to choose which one is the encode and how poor it sounds compared to the reference. It's an objective test that has nothing to do with your hardware because you aren't choosing which one you like best, you are choosing which one is exactly the same as the reference.

        1) Listening tests are, by definition, subjective.

        2) Consider that I make an audio codec which reproduces the audio perfectly even at low bitrates, EXCEPT for a constant hum at 15kHz.

        - Person A plays it back on his cheap sound

    • Re: (Score:3)

      by fbjon ( 692006 )
      These codecs are designed on top of those very quirks of human audio perception. And no sane person runs audio tests in a consumer shop that wants to sell you the expensive gear. Anyway, Subjective audio comparison is the only meaningful way to compare them (apart from models based on human hearing). Controlling for variables is a different problem however, you might argue tests run by random internet visitors are useless, and you might be right. Or you might not, it depends on how large the differences tur
  • I'm surprised iTunes wasn't in the list. Isn't it one of the more popular encoders?

    • Re: (Score:2)

      by Haifen ( 14404 ) *

      iTunes uses QuickTime components, which are in the list.

    • That's because iTunes isn't an encoder. Quicktime is. iTunes is just the library application that uses Quicktime for playback (decoding). Try encoding something in iTunes next time and then go look at the song info. You'll see something like "Encoded with: iTunes 10.4, QuickTime 7.6.6".

  • Self Proclaimed Golden ears should really step up. (Score:5, Insightful)

    by guidryp ( 702488 ) on Sunday July 24, 2011 @08:46PM (#36866920)

    Rather than typical net snobbery against lossy encoders, the self proclaimed golden ears should really help out, they are the ones that can spot encodes a mile away, they should be able help find really good/bad encodes here.

    I found myself humbled when I attempted to help out before. I had a hard time distinguishing anything but the poor encode used as control.

    Really guys this is a chance to help out, or recalibrate your preconceptions about how good/bad modern encoders are.

    Or would you rather just keep up with the unjustified snobbery?

    • Re: (Score:2)

      by Divebus ( 860563 )

      I've got the perfect two guys with absolute golden ears. They could hear the difference between a digital music master and a perfect copy of that music recorded to another audio workstation. They said the image was "smeared". The rest of us engineers couldn't hear any difference at all. Turns out they were hearing clock jitter from the AES signal system. We did a data copy and that solved it.

      Both guys are legally blind, but they can mix audio.

      • Re: (Score:2)

        by guidryp ( 702488 )

        I have no doubt that there are some individual with superior hearing that may have real complaints.

        But I don't any of them are the people posting above and dumping on compressed audio, without even bother to try a simple blind test when presented to them.

        I just did a casual run through of this test and again only the low end control stood out for me.

        These are 96K files. The state of the art has certainly moved on.

        • Re: (Score:2)

          by Divebus ( 860563 )

          Absolutely right. I think 96khz data rate is a threshold where you can start hearing degradations. All these people are doing is testing each other's hearing, not the audio files. We know they're flawed.

          Heh... "blind test"... why didn't I think of that?

          • Re: (Score:2)

            by guidryp ( 702488 )

            Absolutely right. I think 96khz data rate is a threshold where you can start hearing degradations. All these people are doing is testing each other's hearing, not the audio files. We know they're flawed.

            So you add another unsubstantiated, untested proclamation.

            The whole point of this is to find low rate encoders that people can't distinguish.

            To determine that, you need people to test it.

            Instead all we get are baseless opinions and no testing... sad.

            • Re: (Score:2)

              by Divebus ( 860563 )

              And you're doing... what... to find the answer? Whining on slashdot? That's what's sad. I've already got the answer for my compression needs. Do your own testing and let me know how that came out.

              • Re: (Score:2)

                by guidryp ( 702488 )

                And you're doing... what... to find the answer? Whining on slashdot? That's what's sad. I've already got the answer for my compression needs. Do your own testing and let me know how that came out.

                I already did my own ABX testing for my personal needs a few years back and settled into using ~160K VBR.

                I also did a casual test of the samples above as well and I am quite impressed at the progress in encoders. 96K AAC is doing quite well.

                I am just sad that on slashdot, a place where I expect some respect for scientific method, when people are given the chance to test experimentally how current encoders are working out(and optionally contribute data), they instead resort to baseless assumptions and preco

                • Re: (Score:2)

                  by Divebus ( 860563 )

                  That's 160k VBR using which codec? AAC? That's about where I also stop hearing the differences, so I just go to 256k for round numbers. Well, round numbers for a computer, anyway.

                  I may also be fooling myself now because age takes a toll on hearing, but there was a time when there was nothing like listening to a studio master tape. Capitol Records was letting us into their vault to make DVD-A disks about 10 years ago. That's when I started noticing aliasing in the audio - it was actually high frequency conte

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