Noel, CD quality is certainly NOT 128 kbps. That's 128 kilobits per second. CDs are roughly 10 MegaBYTES per minute. Considering that a BYTE is 8 bits, that makes CD quality 80 Megabits per minute. There's 60 seconds in a minute, so dividing 80 Mbpm by 60 gives 1.33 Megabits per second.

WAY more data density than 128 kpbs. A thousand times more data. That's why .mp3 files are so much smaller than their .wav counterparts, which at 16 bit data width and 44100 Hz sample rate ARE CD quality.

.mp3, ogg vorbis, WMA, and any of the other audio data compression schemes use various algorithms and decisions in those algorithms to decide how much of the data to 'throw away' in the compression scheme. One thing .mp3 compression does across the board is simply eliminate all data above 14 kHz. No matter what bit rate is used.

I will agree with you that with some music, and some .mp3 compression, and dependent on the data playback, you can get decent sounding 128 kbps mp3 files. But it is highly dependent on the program material used, compression scheme used, playback system, etc.

For my personal CD collection for playback in my car, I have chosen to use 192 kpbs compression with .mp3 files. I find that I really can't tell the difference between these files and CDs of the same material played back in the car. With 128 kbps files, I can usually hear artifacts of the compression on sibilant vocal sounds, and the high-frequency parts of ride cymbals, crash cymbals, etc.

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