FLAC vs. MP3 - loudness/DSP something's up...

I have begun re-ripping my collection - this time to FLAC. In fact, I have also downloaded a few FLAC albums of CDs that I have that the CDs are trashed.

After uploading some of these flac files to the player, Ive noticed a few things:

1) They DO sound noticably better than most of my MP3s.
2) FLAC files seem to have less "gain" than MP3's. Even if I make MP3s from the same source, carefully - with say LAME and alt -preset -standard.

It seems, in my case, that the MP3 files are "gained up" more than the flac. To the point where, perhaps, some digital clipping is happening? Anyone have comments or insights on this possibility?

I know it sounds strange... But does the player handle the data the same way? I.e. is any of the mp3 data processed before being decoded in some way? Or FLAC? The MP3's I refer to have a "shrill" quality in the upper midrange, and the corresponding flac will not. I now notice that most (but strangely not all) of my mp3 collection has this "quality". (The ones that dont are almost all older, 128kb, non-lame encodes...)

Comments or thoughts?

Jeff

High-frequency waveforms are the hardest to encode and take up the most bandwidth. Your 128kbps mp3s don't exhibit the problem most likely because they were encoded with a highpass filter, which I seem to remember used to be a default in LAME, so they simply don't have many high-frequency noises at all.

From the hydrogenaudio faq:


Why do encoded files get clipped when the original WAVs are not clipped?
Short answer:

1. Quantization errors may cause the signal to clip, and
2. Gibbs phenomenon through the limitation of bandwidth may cause the signal to clip.

http://wiki.hydrogenaudio.org/index.php?title=FAQ#General_Audio_Compression

http://ff123.net/norm.html

This is another reason I put big drives in my Rios and play .WAV files.

Ross