Bitrate or bit rate literally means the number of bits that are conveyed or processed per unit of time. Actually, the unit of time is second, so, the unit of bitrate is bits per second(symbol: bit/s, bps), or kilo bits per second(kbit/s, kbps). WAV is an uncompressed audio format. The bitrate of a 2 channel, 16 bits per sample, 14400 sample rate WAV file is 2*16*44100=1.3 Mbps. MP3 is a compressed audio format. The bitrate of the same MP3 file as the previous WAV file is about 128 kbps, much less than the WAV file. You can adjust the bitrate of a compressed video of audio file. For the same format, lower bitrate means higher compression rate, lower quality and smaller file size.

Many people want to change video bitrate or change audio bitrate to adjust the size and quality. To do this task, a powerful Bitrate Converter is essential.

Just found Faasoft MP3 Bitrate Converter. Have you tried it?