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2nd Multi-Format 128kbps Public Listening Test

Posted by ryuzaki0 on from the music-to-one's-ears dept.

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."

5 of 316 comments (clear)

  1. Re:Ogg! by MikeXpop · · Score: 4, Informative

    Here's insightful. Ogg is a wrapper. It has nothing to do with the quality of the sound. You should be chanting Vorbis.

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    Etiquette is etiquette. He kills his mother but he can't wear grey trousers.
  2. 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.

  3. Re:Objective audio analysis by tashanna · · Score: 4, Informative

    Frequency analysis only gets you part way there. For those who didn't look around at the articles (I'm not refering to you, of course; just some hypothetical /. reader), there are time domain audio effects that are not visible on FFT plots. An example of this is pre-echo. With pre-echo you get a n echo of an upcoming sound (like a drum beat) before the actual sound happens. This can happen when linear-phase FIR filters are used, but is also an artifact of some frequency domain encoder/decoder systems. The FFT is only part of the story.

  4. 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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    Karma: Segmentation fault (tried to dereference a null post)
  5. Re:What ever happened to r3mix.net? Any replacemen by JebusIsLord · · Score: 4, Informative

    The r3mix tuning (--r3mix), while a small step forward, was inherently flawed because of his insistance on tuning based on pictures instead of acual listening tests. As a result, the --dm-presets were invented and improved by Dibrom (the HydrogenAudio founder) along with a multitude of testers. eventually those were included in LAME as the --alt-presets (and in the latest version they just replace the normal --presets). In short, Hydrogen Audio is THE place to go for this stuff now.

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    Jeremy