# Audio Files

The following audio file formats are supported:

- .WAV files: 16-bit mono or stereo (Pro edition also supports 24-bit, 32-bit, and 32-bit float files).
- .AIF files: 16-bit mono or stereo (Pro edition also supports 24-bit, 32-bit, and 32-bit float files).
- .FLAC files: 16-bit mono or stereo files using lossless compression (Pro edition also supports 24-bit).
- .GJM files: 16-bit mono using lossless compression (Pro edition also supports 24-bit).
- .GJS files: 16-bit stereo using lossless compression (Pro edition also supports 24-bit).
- .M4A files: 16-bit mono or stereo files using lossy compression.
- .MP3 files: 16-bit mono or stereo files using lossy compression.
- .AEM files: contain references to audio files to play. .AEM files are generated by MultitrackStudio (see Understanding Audio Editing).

The Mac version can open existing .aac, .ac3, .mp4, .aifc, .caf, .snd, .au, and .sd2 files.

### WAV files

WAV files can be used with almost any program that supports audio. You need a WAV file to create an audio CD.

### AIF files

AIF files are similar to WAV files. They're widely supported on Mac computers but rare on Windows.

### FLAC files

FLAC files use lossless compression to reduce file size.
MultitrackStudio generates native FLAC files. It can read native FLAC files and files using an MP4 container.

On macOS, FLAC support requires macOS 11 or newer.

### GJM/GJS files

GJM/GJS files use lossless compression to reduce file size. They can be used in MultitrackStudio only. The compression algorithm works best if the audio signal doesn't contain loud treble parts. This works well for multitrack recording, since tracks typically have many silent or soft parts, so the file size can easily be reduced to about 70% of its original size.

Note that sound quality isn't impaired in any way by the compression: if you save a .WAV file in .GJM format and then save that file in .WAV format again, you get exactly the same file.

### M4A files

M4A files use a lossy compression algorithm that degrades sound quality. Sound quality tends to be slightly better than MP3.

The Mac version supports lossless ALAC compression.

### MP3 files

MP3 files use a lossy compression algorithm that degrades sound quality. The resulting file size is 3 9% of the original size. This makes the format suitable for publishing your songs on the internet, or sending them via email.

Each time a new MP3 file is created, the audio quality can be selected: Medium, High, Higher, or Very High. These options correspond to 56, 128, 192, and 256 kbps (stereo files) or 32, 64, 96, and 128 kbps (mono files).

### Legacy files

Existing files of these obsolete types can still be read:

- .LST files: pre-MultitrackStudio 5 equivalent of .AEM files.
- .SAM files: 16-bit mono headerless raw data files.