Find one that supports OGG Vorbis (iRiver is an example) and I'll give you a compression algorythm/codec that is near lossless (MP3 for example is very lossy) yet still keeps a good file size. It does this by not putting a restiction on the bitrate, so while it is trying to maintain 212 kbps or less, it will sometimes shoot to 500 to 600 kbps to maintain quality for the highs in a song. If you use this, you will not be able to tell the difference between the original CD and the compressed version (outside of the db loss or quality loss caused by the player itself or your soundcard on your computer).
The players say they max out at 320 kbps, which is fine because they are not floating point based but are instead integer based. This will not affect the playback of a speically encodded ogg file however, so don't worry about it. It is rare that it will need to exceed 300 kbps anyway.
Typical file size over a standard MP3 recorded at 192 kbps will be nearly equal most of the time since it doesn't have a low end restriction either - meaning it will drop to 0 kbps if it can get away with it. Worst case however, add 5% to the file size.
VBR MP3's and standard encoded ogg's do their best to maintain a constant bitrate, even though all ogg (Or most at least) are encoded at a varible bitrate - they will still maintain somehwere close to your desired bitrate at all costs - this is done with streaming in mind. My specially tuned version however ignores this limitation which is why the major increase in quality without much (if any!) increase in file size.
-S
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