MP3 compression artifacts

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Interesting thing I noticed, and that's how the MP3 compression system is thrown bezerk when it is encounters analogue distortion, frequently adding significant digital distortion to the audio. I like to listen to classic rock, much of which is loaded with analog distortion. I MP3'ed "We Won't get fooled again" by the Who. The part in the middle of the song with the organ solor sounds pretty clean, but it's not. There's a hint of distortion, with some phase shifting and other stuff going on in the organ. It's so little distortion that the MP3 encoder doesn't really classify it as "distortion" and process it as such (the way it does, say with fuzz guitar) It tries to process the subtle distortion as legitimiate audio information, and "de distort" it. The result is a few odd overtones and other pitches that were never there on the original. When it's MP3'ed it doesn't sound ANYTHING like it did from the original recording!

I've noticed that the MP3 format is definitely not perfect. I just still hope in the future we will still be able to get un-compressed audio from a real music store. There's been all sorts of talk from music distributors about wanting to move away from CD's and other media for distribution. I'm sorry, but compressed I-tunes just don't cut it for my autistic senses!

What bitrate was your version of the song encoded at? I find that the phase shifting, and other artifacts, ( a ' grainy' or 'artificial' HF response, stray harmonics, etc) are quite noticable when AB'ing MP3 duplicates of CD referance material encoded at 128 KB/sec, less so at 192 KB/sec, much better at 256 KB/ sec, and quite close to CD quality at 320 KB/sec.

You will also find that some encoders are much better than others. --I use either the LAME encoder, or the Fraunhoffer encoder with excellent results.

I also use the LAME encoder, also with excellent results. I've gotten good reviews on them from people who don't like MP3's in general.

To check out my LAME-encoded MP3's, go to http://scoogy.com/maxcreek/

Exact Audio Copy is a very good ripper, and LAME, as always, is the best encoder. I always encode with the alt-preset standard command line switch, and I've never noticed any detriment to the quality of a song.

Dont forget about Ogg Vorbis, Flakk, MPC, WMA and all thsoe other compression types as well.

I usually use Ogg Vorbis for all my music, because it does not have any of the nasty compression artifacts like MP3. OGG's, to me sound perfectly clear at low bitrates, while MP3s are pure crap when they are at 64-128kbps CBR. You could try using VBR mode in MP3 to help get rid of sound anomalies, OR you could just use FLAC (which is lossless).

The most important thing to note about the MP3 format is that it compresses by cutting the high end of the frequency range. Since distortion is created by adding harmonics (extra frequencies that are multiples of the fundamental frequency) MP3s are going to give you artifacts in areas of distortion. Along with anything else that utilizes the higher end of the spectrum, like cymbals and high-hats. Obviously, some encoders work better than others, but it's best to avoid music in MP3 format whenever possible. It was designed to preserve the human voice, and that's what it does best.