Sending your work to others

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Revision as of 14:20, 6 April 2014 by PeterSampson (talk | contribs) ("disk" consistency)
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If you are working with other users, can you send your multi-track Project to them so they can contribute to it? Can you send an audio message with some music and e-mail it to a relative? Or what if you want to open your Project on another of your own computers running a different operating system?

Sending Projects to others

It's quite possible to send an Audacity Project to another person or open it on another computer of your own, so that the Project can be opened in another copy of Audacity with all the tracks, label and envelope information in situ. However when opening the .aup Project file you need to have its associated _data folder with the same name as the .aup file present in the same folder. For example, to send a Project to someone else you could send the .aup file and _data folder in a compressed .zip archive. Free Windows tools to create .zip archives include 7-Zip or IZArc. Free OS X tools include Keka or Apple's built-in compression utility (OS X 10.3 or later). Zip compression is lossless, so does not reduce the space on disk very much. Ask your recipient to extract both the .aup file and _data folder to the same directory then open the .aup file from inside that folder.

In practice, the problem with sending such a folder to someone else is the size of the _data folder. At Audacity's default 32-bit float sample format / 44100 Hz sample rate using lossless uncompressed audio, stereo Projects take 20 MB of space per minute, which rules out sending the project by e-mail.

To send your project, first close it so that Audacity can discard the surplus data which allows undo and redo of edits while projects are open. This way, only the audio for the current state of the project is included. Then use a zip program like those above to place the .aup file and _data folder inside a zip file. Then find a suitable free internet file transfer service to send your zip file. Recommendable services include the following. Check the limitations for free accounts on size and number of uploads, maximum permitted number of downloads, and length of time files are stored for.

Don't forget old-fashioned solutions too if you are still on slow dial-up internet. You can always combine your .aup Project file and _data folder in a .zip file, burn this to a data CD with Windows Media Player or similar then send it by postal mail.

In current Audacity, you can produce a small, compressed project for distribution to others using File > Save Compressed Copy of Project.
  • The audio in the _data folder is in the form of one OGG file per track of the project.
  • The OGG file is very slightly lossy, whereas when saving a project by File > Save Project or File > Save Project As... the .au files in the _data folder are lossless.

Dependencies on other audio files

If you save a standard uncompressed project which contains audio imported into Audacity from a WAV or AIFF file, you must have previously set Audacity to make a copy of that original audio when you imported it, so that it's included in the _data folder. Note that when importing compressed audio like MP3 or OGG, Audacity always copies the audio into the _data folder.

  • When you import a WAV or AIFF there will by default be a warning where you can choose to copy in the file or not.
  • You can always check if you need to copy in files to the current project, and copy them in if necessary at File > Check Dependencies....
  • You can change your preference for future copying in or not in Import / Export Preferences, and you can turn the warning on or off in Warnings Preferences.

Warning icon Legacy versions of Audacity: Prior to 1.3.13 there is no warning on importing WAV or AIFF files, and prior to 1.3.2 there is no "Check Dependencies" menu item. In these legacy versions, make sure you always have WAV or AIFF files copied into the project by selecting "When importing uncompressed audio....make a copy of the file before editing" in the File Formats tab of Preferences.

Sending to someone using a different version of Audacity

Always use the latest version of Audacity if you can. If you or the other party created the project with a legacy version of Audacity, please note the following restrictions.

  • If the person you are sending the Project to has a legacy 1.2.x version of Audacity you will need to save the Project in a 1.2.x version of Audacity, because 1.2.x versions of Audacity cannot open Projects created in 1.3 or later versions.
  • If the person you are sending the Project to has Audacity 1.3.2 or later, they should be able to open a project created in 1.2.x, but ask them to back up the .aup file and _data folder on receipt to be sure. To make a backup, copy the .aup file and _data folder and paste them into a different folder. Once they do save that project in 1.3.x or later and send it back to you, you will need 1.3.x or later yourself to open it.
  • If the person you are sending the Project to uses Audacity 1.0.0 (users on Mac OS 9 are limited to this version of Audacity), you must create the Project in 1.0.0, because 1.0.0 cannot open Projects created in 1.1.0 or later. If that person sends you a Project created in 1.0.0, you should generally be able to open it in 1.1.0 to 1.2.6, but Audacity's conversion of a 1.0.0 Project to the new format used by 1.1.0 or later does not always work. You should not open Projects created in 1.0.0 in current versions of Audacity.

Sending to someone using a different operating system or platform

  • If the person you are sending the Project to is on a different operating platform (for example, you are on Windows and the other user is on a Mac), you must create the Project using Audacity 1.2.2 or later, and the other user must be using 1.2.2 or later. Prior to 1.2.2, .aup Project files are not portable between different operating platforms.
  • Zip formats do not support reliable character encoding, so for the name of the project, labels, track names or metadata, only use A to Z or a to z characters, whole numbers (0 to 9), underscore or hyphen-minus (or use the NUMPAD_SUBTRACT key). Anything else could be incorrectly interpreted by the unzip application on the other operating platform.
  • Also use only A to Z or a to z characters, whole numbers (0 to 9), underscore or hyphen-minus (or use the NUMPAD_SUBTRACT key) if either party created the project on Windows 98 or ME which are non-Unicode systems. This is the case even if both parties are on Windows.

Sending an exported audio file

You can also send an exported audio file from your Project to the other user. Only Project–specific information such as label and envelope data will be lost by exporting instead of saving a project.

To export your Project as an audio file, choose the File > Export... command. Choices:

  • Exporting as a WAV or AIFF file creates a file with no loss of audio quality, but this takes 10 MB of disk space per minute for CD quality (44100 Hz, 16 bit stereo).
  • Exporting from Audacity as FLAC provides lossless compression and reliably reduces file size by about 40% compared to WAV or AIFF.
  • Exporting as an OGG or MP3 greatly reduces the size of the exported file, at the expense of some quality loss.
    • OGG tends to have slightly higher quality than MP3 for the same file size, but not all software players can accept OGG, and most web sites hosting audio files expect MP3.
    • Audacity's default MP3 export bit rate of 128 kbps gives very reasonable sound quality for about 1 MB of space per minute. To compress the MP3 to a still smaller file (at the cost of further quality loss), choose "MP3 Files" in the Export File window, press the Options button then reduce the bit rate in the "Quality" dropdown.

      (In legacy versions of Audacity prior to 1.3.3, go to the File Formats tab of Preferences, and in MP3 Export Setup, reduce the bit rate in the dropdown menu).

      For example, a 64 kbps MP3 would take up 0.5 MB (500 kb) per minute, because 64 kbps is half the default bit rate of 128 kbps.

To export MP3 files you must add the LAME encoder to your computer. Instructions for doing this are at Lame Installation.

For all formats except MP3, you can reduce the exported file size further by reducing its sample rate. Do this by changing the project rate dropdown bottom left of the screen. Reducing the project rate below 44100 Hz is only recommended for speech.

Sending files by e-mail

You should always attach your audio file to the e-mail message. Some e-mail clients can embed the audio inside HTML e-mail messages so that the recipient hears the audio on opening the e-mail without having to open an attachment. However whether the recipient will hear the audio depends on the recipient having an HTML e-mail client (or having HTML enabled without any security restrictions in place). Many e-mail users disable HTML e-mail due to its perceived security risk.

Sending files greater than 5 MB by e-mail is usually out of the question due to server bandwidth and storage restrictions. Some webmail services do allow larger messages to be sent. For example, Gmail allows sending messages up to 25 MB, but this still depends on the recipient's e-mail service accepting large attachments. The best solution is often to use a web-based transfer service like, or, or burn the exported audio file to an audio CD and send it by postal mail.

If you want to burn to an audio CD you need to export 44100 Hz, 16-bit stereo WAV or AIFF files, and tell your burning software to burn an "audio" or "music" CD. For instructions on how to do this, see How to burn CDs. Audio CDs will retain the full quality of the original track in Audacity, can contain 74 – 80 minutes of music and can be played in computers and on any standalone CD player (and some standalone DVD players).

Exporting from multi-track projects

If you have multiple tracks in your Project, Audacity by default will mix these down to a single mono or stereo track when exporting to an audio file. To export separate tracks you can:

  • Use File > Export Multiple and "split files based on tracks"
  • Select the first track, choose File > Export Selection As... then repeat in turn for the other tracks.

The recipient can then shift-select and multiple import each file into separate tracks of an empty Audacity Project.

Alternatively, current Audacity can export the individual tracks in a Project as one multi-channel audio file. So if you had a Project with six mono or left/right tracks, it could be exported as a one six-channel audio file, and any user of Audacity 1.2 or later can open that file and see the channels displayed as individual tracks.

To use multi-channel export, go to the Import/Export section of Preferences and enable "Use custom mix". (In legacy 1.3.2 to 1.3.4 versions of Audacity, this feature may be called "Advanced Mixing Options" or be in the "File Format" or "Audio Files" Preferences, and does not exist in versions prior to 1.3.2).