This may not answer your question directly. It offers some
insights to audio quality and appreciation of quality.
Full Quality http://www.audioboxinc.com/quality.html
Size vs. Quality
The moral of the audio quality story is simple: bigger is better.
Compression may be useful for sending tunes over the Internet on a
slow connection, but extreme compression has no business being
hooked up to a PA system. The solution is to get a bigger hard
drive and to carry fewer songs. Luckily, drives are getting bigger
and less expensive, and music files are staying the same
size.
If you are interested in conducting a less expensive self-test for
compression and MPEG sensitivity, you can try these two
tests:
Radio signal compression vs. CD
If you have a CD player in your car, tune in a station that is
likely to play a song you like from a CD that you own. Listen to
the radio, and have your CD loaded and ready. When they play the
song you have loaded, listen to the radio for a few seconds, then
press play on the CD. The perceived "quality gain" that you should
hear represents the difference of quality between CD audio and
radio quality. The FM signal quality is significantly lower than
the quality allowed by modern computer compression technologies, so
the change in quality should be very evident to the human
ear.
For this test to be accurate, the volume level of the radio and the
CD must be equal. A difference in volume introduces other factors
that change the perceived audio quality.
MP3 vs Cassette Quality
If you are tired of hearing how MP3 files are "CD Quality," you can
test your ears to see if you can tell that MP3 is LESS THAN TAPE
QUALITY. Record a song onto your computer, but don't compress it.
Make a cassette recording of this song. Now, compress the song to
each available "CD Quality" level your encoder has. Typically,
these bitrates would include 128, 112, and 96 kbps.
Record the MP3 files onto another cassette. Now, using a dual-deck
system, switch back and forth between playing the recording of the
uncompressed music and the MP3 encoded music. Be your own judge,
and see if you really can hear the difference.
Now, if you can hear the difference on a cassette tape, shouldn't
you ask yourself how close to "CD Quality" the compression format
you chose is?