>> AT9 file

AT9 file format description

Many people share .at9 files without attaching instructions on how to use it. Yet it isn’t evident for everyone which program a .at9 file can be edited, converted or printed with. On this page, we try to provide assistance for handling .at9 files.

1 filename extension(s) found in our database.

.at9 - Sony ATRAC9 Compressed Audio

The AT9 audio files are related to FFmpeg. AT9 file is a Sony ATRAC9 Compressed Audio. Adaptive Transform Acoustic Coding (ATRAC) is a family of proprietary audio compression algorithms developed by Sony.

Audio files
- / -
Sony ATRAC9 Compressed Audio related extensions:
Chinese AVS Video
DTS Core Audio Stream
DTS-HD Master Audio
Microsoft DV-AVI Video
FFmpeg Video Stream
FFmpeg Presets Data

Naturally, other applications may also use the .at9 file extension. Even harmful programs can create .at9 files. Be especially cautious with .at9 files coming from an unknown source!

Can't open a .at9 file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize a filename extension, you receive the following message:

Windows can't open this file:


To open this file, Windows needs to know what program you want to use to open it. Windows can go online to look it up automatically, or you can manually select one from a list of programs that are installed on your computer.

To avoid this error, you need to set the file association correctly.

The .at9 file extension is often given incorrectly!

According to the searches on our site, these misspellings were the most common in the past year:

ar9, at, ati, ato, atp, ta9

Is it possible that the filename extension is misspelled?

Similar file extensions in our database:

Visual Studio ACT Project
Alphacam Lathe Post Data
Microsoft Accounting Import
Sony ATRAC3 Compressed Audio
ETCBC Analyzed Text Data
Automise Project

Operating systems currently supports the following operating systems:

Windows XP/Vista, Windows 7/8, Windows 10, CentOS, Debian GNU/Linux, Ubuntu Linux, FreeBSD, Mac OS X, iOS, Android

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