Need Some Help? Maybe a Video will explain it better
 MP3Gain - Finding the Volume of your MP3 recordings it is easy to check the decibel level of any mp3 recordings  Oh Dear! I deleted my recording! If you've been told to edit your recording, this is how to find it in our server Changing Your Bit rate have you been told your bit rate is wrong? well, if you use Audacity, it is easy to fix.
 Amplifying a File with Audacity