I personally record all my MP3's at 320kbps. I know it may be overkill but I like the detail. A typical 5 minute-ish song/track is around 11 to 13 MB. I read many years ago that MP2 was a better sounding but lacked the compression of MP3. I think I could tell the difference before (listening through $150 german headphones), but now I don't think I can hear the difference between the 320kbps MP3 and 320kpbs MP2. Perhaps the encoding schemes are better for MP3 than they used to be, I don't know. I remember downloading a command line MP3 encoder for OS X that claimed to encode using better psycho-acoustics than current MP3, but I never used it, got filled under some directory somewhere and archived to a CD, probably never to be used, but nice to have "just in case".
I wouldn't recommend re-encoding unless you have to. For me and my CD burner, I can copy an audio disk faster than encoding MP3, but I only make my MP3 for my use and no one else's. I had hoped to connect my Mac to my home stereo but never did. I didn't for fear of being disappointed in the sound quality coming from the Mac. My home stereo cost about $10,000 and I expect to hear serious flaws, which I wouldn't be happy with so I didn't even bother. Incidently, you can hear the difference between an original audio CD and the burned copy of an audio CD - the difference is due to timing errors that are introduced into the CD and picked up by D/A converter.
My stereo system:
High-end Philips (Made in Denmark) purchased 10 years ago from Paragon Sound in Toledo OH.
FR930 Receiver/amplifier($550; 150W/channel, Dolby ProLogic [when it was new!]).
CD 950 Compact Disc Player ($640; Frequency range: 2Hz-20kHz; Dynamic range: 108dB; Signal to noise ratio: >115dB; Channel separation: >110dB; Total harmonic distortion: 0.001%; Bitstream conversion 128X oversampling, 1 bit, 3rd order noise shaper). This unit contains a commercial laser. I will die before the laser burns itself out. Optical digital output goes directly to the DCC digital input.
Digital Compact Cassette (DCC) recorder/player (records in MP2 format, sound specs not as good as the CD player). Cost $1000 - yeah, I know, waste of money, right after I purchased it CD-R were introduced on the market.
BostonAcoustics VR960 speakers (Made in America; $1000/pair, 50 lbs each with one 8 inch powered sub in each speaker, Dolby Digital inputs, 1 inch Lynnfield tweeter, 4.5 inch mid range. Speakers rest on 2 inch long spikes going into my carpeted floor.
http://www.bostonacoustics.com
http://www.bostonacoustics.com/ProductsPage.asp?ProductID=9&SpecID=1&SeriesID=16
Transparent Cable Music Link interconnects (Made in America; connects the CD player to the amplifier). These cables are approximately 3/8 inch think and are made with high purity copper with high pass and low pass filters that terminate at the cables end in a small black box($150/pair). Only frequencies in human hearing range are allowed to pass through the cables.
http://www.transparentcable.com
Transparent Music Wave speaker cable (Made in America; connects amplifier to speakers). These cables are approximately 1 inch THICK, have high purity copper with high pass and low pass filters that terminate at the cables end in a large 7 inch black box($870/pair). Only frequencies in human hearing range are allowed to pass through the cables. Cables are only 10 feet long.
http://www.transparentcable.com
Bang & Olufsen turntable. ($550 WITHOUT the diamond needle). For VINYL records!!! MM4 Eliptical diamond cartidge ($100). The MM1 diamond cartridge was $500 - too expensive for me.
Other components will not be listed. This is long enough.
When I listen to my music, I don't just hear it, I FEEL it, literally, the bass is incredible, but not overbearing - very tight bass.
chemistry_geek