Vorbis - Jun 2003 - The effects of encoding repeatedly

I just did this experiment where I took an audio clip, encoded it to Vorbis
q4, decoded it to wav, and repeated several times.  I also did the same with
MP3 @ 128k.  Here are the resulting files, if anyone is interested in the
results.  Clip1 is the first encoding, and Clip8 is the eighth.

http://mywebpages.comcast.net/swmarks/vorbis/clip1.ogg
http://mywebpages.comcast.net/swmarks/vorbis/clip8.ogg

http://mywebpages.comcast.net/swmarks/vorbis/clip1.mp3
http://mywebpages.comcast.net/swmarks/vorbis/clip8.mp3

It appears that vorbis dumps in a lot more high frequencies when encoding,
in comparison to mp3.

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On Sat, 28 Jun 2003 23:40:53 -0400
Paul Marks <pmarks@purdue.edu> wrote:
> It appears that vorbis dumps in a lot more high frequencies when encoding,
> in comparison to mp3.
Know problem. It's the main issue of the current encoder. The lower the
quality, the higher the boost. Starting from -q6 the effect disappears.

<p>
--
Bye.
   Giuliano.

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