Originally posted by: ScottyB
MP3s usually sound better to me than CDs. I always here background noise with a CD but not with MP3s. The noise sounds like a slight humming or wind tunnel or something.
That's highly unlikely. MP3 files should store all the little details that are audible on the CD/WAV. That's not to say they are transparent - the MP3 format is predisposed to artifacting because most don't know how to create a proper file - but audible background noise should be retained in the MP3. If it isn't then the encoder that created the MP3 is inferior.
Some guidelines:
For best MP3 quality (at a reasonable bitrate), use LAME 3.92+ with --alt-preset standard as the sole switch. If you want to knock down bitrate a little more, add the -Y switch...this essentially limits encoding to 16KHz in most cases (MP3's 16KHz+ subband doesn't have a scalefactor so if you need to store information in this subband, you can't use a scalefactor for any of the other bands. This means excessive bitrate bloat.)
If you must make the standard 128kbps MP3, use a FhG encoder like fastenc. LAME can be used as well but it's possibly not the best at 128kbps CBR.
ALWAYS USE JOINT STEREO. Stereo mode is inefficient and limits quality.
If you don't require MP3 and appreciate top quality, use MPC and its --standard profile. Very few can differentiate a standard MPC file from the original...and the typical bitrate is livable 170-180kbps. If you have low bitrate needs, Ogg Vorbis is a great choice. I recommend using the -q 2 switch, which will produce files around 96kbps.