256kbps CBR MP3 vs 320kbps CBR MP3 for best quality?
 

I run an audio conversion program that can convert my albums ripped in flac to mp3 for my ipod. I read debates online about 256 cbr vs 320 cbr (the highest cbr bitrate). I so far have gone with 256 cbr mp3 for maximum compatibility. I read that 256 cbr is a good rate. I thought since mp3 is lossless anyway, that 256 will not be a big deal from 320. But some online say there is a big difference. Is there? I wanted a good combo of compatibility, size & quality.

The differences between 256kbps and 320kbps is really negligible. The quality of the compressor (i.e., FFMPEG vs Fraunhofer) is more important at that high level of bitrate -- assuming a standard 44.1kHz stereo music file.

VBR vs CBR is also more important. While VBR should be better in theory, it doesn't play nice with playback hardware or software, so always choose CBR for compatibility's sake.

Amazon sells most of its music as 256kbps, as does iTunes -- at least last that I paid attention. I've not bought an MP3 in a few months now.

Most people who would insist 320 sounds better than 256 are likely overlooking lots of secondary factors. They're just jumping to conclusions without actually analyzing all possible variables, and scientifically forming theories based on controlled experiements (i.e., the scientific method, which most people are taught in junior high school).

If Amazon and iTunes have decided that 256kbps CBR is a good balance of quality/size/compatibility, then I think it's safe to assume it is. ;)

It's been a while since you've posted. Hope you're well. :)

For audio quality, the archive preset of lame has been tested by the experts at Hydrogen audio, it's going to be very good quality. I haven't had any problem with variable bitrate.
Can you give me an example of hardware/software where it caused a problem?
Off the top of my head, it shouldn't be possible, because each frame is considered independantly and can be any bitrate the device accepts. There is compatibility issues with layer 2.5 frames, however. I had a player that wouldn't do 8Khz mp3's for example. It was a problem for me as I wanted to encode huge audiobooks in the lowest possible quality.

There's also a tool which will compact mp3's losslessly; these CBR files have redudant info which can be recoded. I saved tons of space in my collection with no loss at all. I can't find the tool right now though...