Easily convert your MP3s to AAC for music on the go!
AAC stands for Advanced Audio Coding and is officially the successor to the hugely popular (and still widely prevalent) MP3 format. AAC was developed by Fraunhofer, AT&T, Nokia, Sony and Dolby and offers a number of improvements over MP3. Okay so you clicked on that link and you understood NOTHING (like me!). Fear not peeps, the tech warrior is here to help 
Simply put, AAC is better than MP3 in every way. Though it is a lossy format like MP3 (some data is dropped during encoding, but that change is mostly not picked up by the human ear), in my personal experience, AAC sounds much better than MP3s in lower bitrates. Lower bitrates = Smaller filesizes = Lotsa songs on your memory card!
AAC conversion, however, was not easily implemented very easily in those days. Nero (yup) came out with a free AAC encoder and soon it was being used by many popular audio converters (like dBPowerAmp). However, dBPowerAmp ain’t free. So then I looked around the Interwebs for anything that would let me convert my MP3s to AACs for free. Suddenly I realized my favourite music player (Winamp 5) has a format converter built-in! So here I’ll be showing you how to convert all your music files (not just MP3s mind you!) to AACs.
If you don’t have Winamp yet, grab it here. During setup, make sure you select the Format Transcoder option. Now fire up Winamp and add all your tracks. Select the ones you want to convert, right-click on them and select Send to > Format Converter. The Configuration window shows up. Under Encoding Format, select the MP4/aacPlus (HE-AAC) Encoder. Then choose your preferred bitrate (anything between 64 kbps and 96 kbps should be good). Once you click on OK, the conversion process starts and.. erm.. ends. And there you have it!
I’m adding a screenshot guide (as usual) below. If you already have Winamp 5 installed but the Format Converter tool is missing, download the 2 plugins provided below the screenshots and put them in your Winamp/Plugins folder.
Format Transcoder + AAC Plus Encoder
Download these two DLL files and put them in your Winamp/Plugins folder.
Bonus Download – LlamaSutra
The Winamp skin featured in the screenshots. You’ll love it!
Note that the output files will not have a .AAC extension, but instead, .M4A. M4A is simply a container format for AAC. Whats a container format? Oh forget it! Just copy the songs to your device and enjoy 
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Tagged as mp3, nokia, winamp + Categorized under Technology, How To | »
Tried it out and its absolutely wonderful Pras!
Now I can have all the songs I want in my mp3 player without any loss in quality! Gr8 work 
@Karthik M: Glad that it helped. Have you checked if your player supports AAC? If not but you still wanna reduce file-sizes, try reducing the MP3 bitrate (though not recommended)