Music play function is newly added to NDSi, actually it is for fun and is nearly real music game.
Only AAC music is available currently(whether other formats will be available unknow). NDSi will identify AAC music in any location in SD card. NDSi records are also available.

Let me introudce how to “play” the record of NDSi first. Choose the obvious record option and select one of the “balloons”, then click the red circle on the bottom screen(REC record icon) to start the record, the length of the record is 10 second, and unable to transfer to the SD card, so one NDSi can keep 18 10-second records at most. The record can be played reversely which is relatively funny.
When playing the record you can select one of the two options on the bottom screen to “play a game”, let one on the left is for adjust playing speed and inflection, the one on the right is for switching sound effect.

It is simple to adjust playing speed and inflection, in the pic below the abscissa axis is playing speed, it plays faster from left to right. The vertical axis is tonality which rise from bottom to top. Select one point in the coordinate axis with the touch pen to adjust playing speed and tonality.

There are 4 sound effects for record: parrot which change all former audio into parrot’s sound; fan which add a fan effect when listenning to music; harmony which add sounds of different tonality to former sound; bugle which is similar to parrot.

Now let me introduce how to “play” AAC music.
Put AAC music in SD card and you can play the music on NDSi, which has more fun than record. There are visual effect when play AAC music while wave frequency spectrum only for record.
Talk about favorite music collection first. Choose one music and click the “お気に入り” option on the right bottom on the bottom screen to add this music into favorite collection.
3 levels of favorite collections are available for users to find their favorite musics quickly. You can only collect 10 musics in the “BEST 10” favorite, and 100 musics in other two favorites.
Of course if every music is selected carefully by users and there is no best one, choose the “おまかせ”option(the first one) to play randomly.

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