Ubuntu Unleashed

SoX is the swiss army knife of sound processing programs. SoX is a command line utility that can convert various formats of computer audio files in to other formats. It can also apply various effects to these sound files during the conversion. As an added bonus, SoX can play and record audio files on several unix-style platforms. SoX is a general purpose sound converter/player/recorder that supports the following formats:

• RAW sound data in various data styles
• RAW textual sound data
• Amiga 8svx files
• Apple/SGI AIFF files
• SUN .au files
  • PCM, U-law, A-law, G7xx ADPCM files
  • mutant DEC .au files
  • NeXT .snd files
• AVR files
• CD-R data (music CD format)
• CVS and VMS files (continous variable slope)
• GSM raw data (with optional library)
• Macintosh HCOM files
• Amiga MAUD files
• MP3 files (with optional external library)
• IRCAM SoundFile files
• NIST SPHERE files
• Turtle beach SampleVision files
• Soundtool (DOS) files
• Yamaha TX-16W sampler files
• Sound Blaster .VOC files
• Ogg Vorbis files (with optional external library)
• FLAC files (with optional external library)
• Dialogic/OKI ADPCM .VOX files
• Microsoft .WAV files
  • PCM, U-law, A-law, MS ADPCM, IMA ADPCM, GSM, RIFX (big endian)
• Psion (PDA) Record.app files and A-law .WVE files
• Maxis XA Audio files
  • EA ADPCM (read support only)
• Record and Play audio on various Unix platforms.
• null file type that reads and writes from/to nothing.

Ok Lets get to converting shall we?
sox myfile.mp3 myfile.ogg
The above command converts mp3 to ogg which is a cleaner format to use, you can use this command to convert files to any format above by just adding the file extention you want it converted to.
Then we can play the ogg file right from the command line and add a lil extra bass :)
play myfile.ogg bass +3
More information can be found on SoX on the developer's page here