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Wiki > Main > SoundCodecs > SoundCodecNSF

NSF (NES Sound Format)


The NES Sound Format (NSF) is a chiptune format for 8-bit Nintendo games. Full specs are at

NSF files are similar to SID files (Commodore 64 music), in that they store multiple tracks in one very small .NSF file. Sound effects are sometimes included in NSF files as well.

An NSF file is actually a ROM for an NES game with all data stripped away, except for the audio engine and audio related data.

There is also the related NSFe (Extended NES Sound Format), which allows for individual track titles and listings. It also allows for marking of tracks that should be ignored by the player.

Current Status

NSF support was added to SVN on 25 Jan 2007. Runs in realtime on all supported targets that support software decoding. Track selection works, but requires that Repeat is set to One. (A note here, track selection only works one way, going forward. Skipping back will skip forward for the first three tracks or so, then will begin playback at the first track again. - AlexVanderpol)

(Also of note: A solution to track selection is to navigate the NSF using "seeking", which works going both back and forth. - RobertMenes)


Playback on most files seems to be accurate to the sound produced by the actual games, though I've run into one that sounds rather horribly distorted (may be a bad rip?), and I've discovered that some games seem to have hidden music tracks that don't actually get used in the game. - AlexVanderpol

Playback is fairly accurate for US NES soundtracks, which use the basic NES sound channels, however, Japanese Famicom soundtracks from the Famicom Disk System, or using the extended sound channels offered by various custom chips included in Konami (and other developer) games, will be missing those channels in the rockbox NSF emulation. However, the US equivalents which have been recomposed for the NES will work fine. An example would be the Japanese soundtrack to Castlevania III, which uses 8 channels, and the American, which uses the original 5 channels only. Current mappers not supported incl. VRC6, VRC7, Namco106, FME-7, and Famicom Disk System - DavidDineenPorter

CategorySoundCodecs: NES Sound Format (NSF)
r5 - 23 Apr 2008 - 03:26:42 - DavidDineenPorter

Parents: SoundCodecs
Copyright by the contributing authors.