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Public AAC Listening Test @ ~96 Kbps [July 2011].
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).
What, no comparison with LAME? How lame.
Life is not for the lazy.
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.
All hope abandon ye who enter here.
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 as contender for the Free Software community would IMHO have been more relevant.
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?
For you, probably nothing. But some people have inquiring minds. They are the reason we don't all live in caves banging rocks together.
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.
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.
Putting syrup in coffee is some form of blasphemy.
They are the reason we don't all live in caves banging rocks together.
The rock-bangers created Ogg.
When they came for the communists, I said "He's next door. Take him away. Goddam commies."
The Hydrogen Audio Forums tests have traditionally used a sound methodology, it would probably be worth reading up on it 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.
In a fair world, refrigerators would make electricity.
I agree that the results are interesting, but in an age of 3TB hard drives and 8GB low-end MP3 players, I'm sure as hell not ripping to 96kbps! :)
I have to assume this is for streaming...
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
iTunes uses QuickTime components, which are in the list.
Look somewhere else for a sig.
in my experience, the equipment attached to your skull is more important than the equipment you purchased.
I've seen people with complete CRAP gear ABX at higher bitrates than I can, and I've got a pretty stout rig.
I too had this same question awhile back. Why doesn't HA test commonly used codecs at, say, 192kbps or 256kbps?
The answer? the tests fail because nobody can tell the difference. they make for very boring results.
they run the test at 96kbps because they get usable results. people over a wide range of sound systems and hearing conditions can provide usable responses.
What would you do with that data? hard to say. you can't really extrapolate that, say, if codec A is better than codec B at 96kbps, the same will hold true at 192kbps. In fact, I've seen the direct opposite of that in past HA tests, where various codecs trade the lead depending on bitrate.
So "who is 96kbps for?" I don't know. but "why test 96kbps?" that's easy.
Ah the audiophile mindset, if someone can't hear the invisible differences I hear then the problem is with them or their gear, because they differences are there I swear it. First of, you've got more than a passing interest if you sit around ABX testing audio codecs for any length of time, people with crap equipment might try it out a round or two but will have left long before they become more than statistical noise. The other good reason is that they tested this, long ago as MP3s were becoming popular. Top people, top equipment, around 256 kbps MP3 they couldn't tell it apart from the CD. Since then we've had better formats (AAC) and better encoders, plenty of edge cases ironed out... if you seriously think you can tell a 256 kbps AAC from iTunes and the CD apart, I'd pay to see you do it under controlled conditions. On a no cure, no pay basis of course - because I seriously doubt you could.
Live today, because you never know what tomorrow brings
"Shill" is not a synonym for "people I don't like".
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?
which platform has a 40mb install limit? that sounds stupid.
Wealth is the gift that keeps on giving.
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.
Well it's better then methane audio, that just sounds like shit!
It's not just audio as such that can be encoded at low bitrates, more important is the audio track emdedded in a streaming video. The video is already hogging bandwidth just to look halfway decent, especially if streaming over a mobile connection, so you would want the best low-bitrate audio encoder to go with it.
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
No, it's so they can actually tell the difference. If they used 256k/s they would reveal that there's absolutely no audible difference between the lossy and lossless samples, let alone between the various lossy ones.
Podcasts, internet radio and other streaming media maybe ?
Those schmoes don't really frequent hydrogenaudio.
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
the download limit for the 3gs over the 3g network is 20MB over that it must be downloaded over wifi.
The low anchor encoder is pretty bad, but likewise that is the only one I can detect. Good thing it is there or I wouldn't be sure the test is working. I think all the samples are correct. They are not messing with us.
Chalk it up to some combination of the encoders being that good and our average hearing.
Too bad none of the guys with super hearing were brave enough to give it a shot.
I thought 96 kbps was "lo-quality" for internet radio and other streaming audio since at least 2004 or so...
You've hit the nail on the head. In the old days of MP3, 96kbps was considered a "low quality" bitrate. We're now many years later, and various encoders have matured to the point where some of us feel that it's worth testing to see how they fare.