Re: Re: [Harp-L] Re: music and perception

[Garry Hodgson <garry@xxxxxxxxxxxx>]

Ken Deifik <kenneth.d@xxxxxxxxxxxx> wrote:

> Of greater relevance may be the whole MP3 thing.  The folks who developed 
> it are said to have used the idea that our ears didn't hear everything in a 
> wav file.  There is apparently a psychological component in there, too.

i believe all of the lossy compression formats (aac, mp3, ogg vorbis) use
psychoacoustic models to remove sounds that you can't hear to achieve
greater compression.

> M4a sounds so vastly much better - to me - than MP3 and WMA now that I can 
> often tell which type of file I'm listening to in a couple of seconds, and 
> MP3 and WMA just bug the heck out of me quite often.  M4a absolutely never 
> sounds lousy to me.

without knowing bit rates, constant vs. variable bitrate encoding, etc, it's not
useful to compare two encodings.  there are so many factors that go into it.
everything is a tradeoff of space vs. quality.  more bits costs you more space,
but gets you higher quality (oversimplified).  and most consumers don't 
really care about quality.  they'd still be buying prerecorded cassette tapes
if they were convenient.  you'll notice that archive.org offers 64Kb MP3 and
VBR MP3 versions of its shows, as well as Ogg Vorbis.  the latter has the
advantage of being unencumbered with intellectual property issues.

i haven't really kept up with the current state of the art, but just settled on 
using the same settings that archive.org uses for their MP3 VBR formats.  
as long as your encoder is better than your ears, life is good.