Here is a tutorial which explains the process of converting mps to aac:http://www.iskysoft.com/topic-ringtone/convert-songs-to-mp3-aac-m4a-in-itunes.html
I need a software to convert from mp3 to aac with these qualities:
Format: AAC
Format/Info: Advanced Audio Codec
Bit rate: 50.1 Kbps
Codec: AAC LC
Codec/Family: AAC
Codec/Info: AAC Low Complexity
Bit rate mode: CBR
Bit rate: 50.1 Kbps
Channel(s): 2 channels
Sampling rate: 22.05 KHz
Resolution: 16 bits

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