Originally Posted by h1a8
As far as I'm concerned It's impossible to tell a difference between 256kbps vs. lossless. I challenge ANYONE to pass a double blind test with 256kbps vs. any lossless codec with any source of their choice and pass with significant accuracy. From all the years I've been researching the subject I've heard of no one who successfully did it. All I hear is people claiming to hear a difference without ABX and thus succumbing to the placebo effect. The only way to be sure is to double blind test (ABX).
I saw a post somewhere with somebody claiming to 10/10 identify 320 kbps CBR LAME 3.98 from lossless. (But there was no reported difference for most tracks, just one particular sample used.) This is definitely the exception to the rule, but I would be cautious about suggesting that it can't be done. Occasionally you'll run into some music just doesn't compress well and foils the encoder.
The vast majority of the time or perhaps 100% of the time for many listeners and setups, your standard 320 kbps mp3 or LAME -V0 will be transparent though. Some tracks, I can 9/10 ABX LAME -V1 or so from lossless, and my hearing is not that great. I'd call the difference very subtle most of the time though. Typically that's the experience of most honest people testing themselves blind. However, I think the difference is indeed a little more obvious to people that can actually hear 20 kHz and a little bit higher, since the standard lowpass filtering done in the encoding process (though that's a parameter that can be changed) makes more of a difference to them.
I'd agree that unless you're a perfectionist or want the original for some kind of archival purposes, I would think the energy of hunting down lossless is likely not worth the small (most likely indistinguishable, but see for yourself) difference, if you already have some kind of 256+ kbps lossy format.Edited by mikeaj - 6/20/11 at 10:13am