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2nd Multi-Format 128kbps Public Listening Test

technology is sexy writes "Roberto Amorim has launched his latest public listening test evaluating the performance of different audio codecs at 128kbps, among them Apple's AAC implementation (used in iTunes), LAME, Ogg Vorbis fork auTuV, WMA, Musepack and even Sony's Atrac3 format, which is soon to be used in their own music store. Read more on Hydrogenaudio and check out the results of prior tests. As opposed to most evaluations of audio codecs, this is a scientific test adhering to ITU-R BS.1116-1 as much as possible while still allowing everybody to participate."

9 of 316 comments (clear)

  1. Listening test? by Anonymous Coward · · Score: 5, Funny

    Never heard of it.

  2. Re:Honesty of responders by Per+Wigren · · Score: 5, Insightful

    Great, now all the ____ fanboys are going to forge results to make their codec look good. Talk about useless tests.

    Not possible. All you will get is a bunch of WAV-files, you have no way to tell which file belong to which codec.

    That said, I don't care which codec wins the test because Vorbis is still the only one free from patents and the margins are so incredibly small.
    Vorbis will win for me even in the unlikely scenario that it comes out last.

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  3. Re:Objective audio analysis by trentblase · · Score: 5, Interesting

    Because "human auditory capacity" is not fully understood. Sure we can give standard frequency response graph, but most of these codecs take advantage of psycho-accoustic hearing models -- where certain frequencies mask other frequencies in our perception. Since this is a developing field, objective listening tests could really help determine what's working and what's not.

  4. Re:Ogg! by Anonymous Coward · · Score: 5, Insightful

    I wish there was a filter that scored any post with the words "You're new here, aren't you?" -5 stupid joke.

  5. Re:Objective audio analysis by The+Clockwork+Troll · · Score: 5, Insightful
    That is a great idea in theory, however there is much debate on how psychoacoustics work, i.e. what information really "needs" to be there in music in order to be perceived.

    For example, conventional wisdom says that the human ear cannot detect sounds above roughly 20kHz, yet there is at least some anecdotal evidence that higher order harmonics shape what we hear.

    If "normal" human auditory capacity was a completely decoded topic, there wouldn't be nearly as much a need for different approaches to music compression (it would be a much simpler problem with fewer possible solutions)

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  6. Re:Objective audio analysis by Anonymous Coward · · Score: 5, Informative
    The purpose of a "perceptual" encoder such as MP3 is to remove the frequencies one cannot perceive. The frequency graph therefore need not be the same as the original and yet the encoded version may not be distiguishable from the original.

    Also, a frequency plot tells us nothing about the phase or frequency distribution at certain times in the signal. I can make a sine sweep that would match exactly the spectrum of a pop song, but obviously would sound nothing like it.

    There are ways of objectively measuring the performance of perceptual encoders, but frequency analysis isn't really one of them.

  7. Re:Ogg! by Neil+Blender · · Score: 5, Funny

    I wish there was a filter that scored any post with the words "You're new here, aren't you?" -5 stupid joke.

    I, for one, would welcome our new filter overlords.

  8. Sound quality is in the speakers by Anonymous Coward · · Score: 5, Insightful

    When you listen to compressed audio over inexpensive speakers / headphones, you can't hear the difference. With my Sony Studio Monitor headphones, I lost the difference at about 250k with mp3, so I started using 320K as that was the best at the time. Then I bought $2000 Martin Logan Mosaic Speakers, and the original CD was clearly better than even the 320K bitrate. So now I only do lossless compression. That's fine at home, but in any other environment, there's usually so much noise and distractions that even if you had excellent headphones or speakers, you wouldn't appreciate that little difference lossless brings over 256K or even 128K.

  9. Re:Okay... by sploo22 · · Score: 5, Informative

    DON'T CLICK THE LINK!

    The sad thing is that somebody went to the trouble of putting together a perfectly reasonable, logical post just to throw in a porn link. *sigh*

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