first go to iTunes next open the file where you save the song then go to itunes DJ and drag your song in their and when the song is already in itunes right click on the song and you will see create aac file then go to recently added in the last one that's the song that is acc file
aac is a type of file format, just like mp3 is.
You need to change the music format to AAC.
In iTunes Right Click on an MP3 file listed in the Library and select Convert to AAC from the menu that appears.
To downgrade an AAC (MP4) to an MP3 file open iTunes Preferences and select the Import Settings in the General section. Change the Import Using: option to MP3 and set the Settings to the desired quality. In the iTunes library right click on the AAC file and select Create MP3 version from the menu.
AAC files are usually smaller with better sound quality than an MP3 file.
Considering that you are talking about media player format i.e. .aac I would what supports such file format are media player. So, media player over Android supports .aac format.
The AAC file format is all I know. Maybe the only one.
The phrase "you cannot import a rights-protected AAC audio file" means that the AAC audio file is protected by digital rights management (DRM), restricting its use and distribution. As a result, the file cannot be transferred or opened in certain applications or devices that do not support the necessary authorization. This protection is intended to prevent unauthorized copying or sharing of copyrighted material.
MP3, WAV, AAC, Apple Lossless, MPEG4, AIFF
MIDI Files can be converted into an AAC file but an AAC file cannot be converted to a MIDI File. MIDI Files are data files made up of different instrument sounds assigned to a MIDI channel. The sounds (instruments) are always separate and can be individually edited. AAC song files are an 'Audio' File - like a song you would hear on a CD or an MP3. These files cannot be converted to MIDI Files as they are a 2 channel audio file. The easiest way to explain this is: You want to bake a cake. The completed cake will be the AAC file (or an MP3, WAV file etc..). The flour, eggs milk and other ingredients that are going into the cake are the individual instruments, like Drums, bass, guitars, keyboards and so on. At this stage, you have the means to create a MIDI File because the individual parts are separate from the whole (cake). However, once the ingredients are mixed and baked, then the cake is whole and the individual parts that went into the cake no longer exist. In short, there's no turning back once the audio file is recorded and saved in the audio format (AAC, or MP3, WAV etc).
only if it is a aac file if you want to play it on your dsi.mostly all you have to do to change it into an acc file is you right click the song you want click "change to acc" then wait tofr it to convert the just drag on onto the correct folder on the sd card.
Music playback file formats: AMR, AMR-WB, MIDI, MXMF, MP3, AAC, MP4/M4A/3GP/3GA(AAC, AAC+, eAAC+, AMR, AMR-WB), X-Tone, WAV(PCM, a-law, mu-law, ADPCM), WMA(WMA9, WMA10) Video playback file formats: .mp4, .3gp Ring tones: AAC, eAAC, eAAC+, MP3, 64- Midi, WMA, WAMR, MXMF wallpaper: swf