Sending your work to others
You may be working with a number of other users and want to send your multi-track Project to them so they can contribute to it. Or perhaps you created a five minute message with some music and want to send it to a relative by email for their birthday. Is either possible?
Sending Projects to others
It's theoretically possible to send an Audacity Project to another person so they could open the Project in their own copy of Audacity, with all the tracks, label and envelope information in situ, but it requires you to send them both the .aup Project File and the associated _data folder with the same name. These could be included in the contents of an attached .zip folder compressed with Winzip or similar program.
In practice, the problem is the size of the _data folder. At Audacity's default 32 bit float sample format and 44 100 Hz sample rate, stereo Projects take up 20 MB of space per minute, and more as soon as you start editing them. This rules out most email transfers. You can transfer larger files over the internet with a service like yousendit.com but for very large files this is unlikely to be free. For example, the yousendit.com free service permits sending files up to 100 MB in size, with a charge for larger files. However you can always combine your .aup Project file and _data folder in a .zip folder, burn this to a data CD and send it by snail mail.
There are other restrictions if you want to send an Audacity Project to another user:
1) If the Project contains audio data that was 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. You set this option on the File Formats tab of Preferences: ("when importing uncompressed audio....make a copy of the file before editing").
2) If the person you are sending the Project to has a 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.x versions. If the person you are sending the Project to has Audacity 1.3.2, the other person should be able to open it even if you created it in 1.2.x, but ask them to back up the .aup file and _data folder first to be sure.
3) 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 saved in 1.0.0, you should 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 is not always 100% reliable. You should not open Projects created in 1.0.0 in the Beta 1.3.x versions of Audacity.
4) If the person you are sending the Project to is on a different operating platform (e.g. you are on Windows and the other user is on a Mac), then both users must be using Audacity 1.2.2 or earlier because prior to that version Project files are not portable between different operating platforms.
Sending an exported audio file
You can always send an exported audio file (such as an .MP3) from your Project to the other user. If your Project only contains one stereo or mono track, only Project–specific information such as label and envelope data will be lost by doing this. But if you have multiple tracks in your Project, Audacity 1.2.x will always mix these down to a single mono or stereo track when exporting to an audio file. To get round this you can:
1) send each track from the Project as an individual audio file. The recipient can then shift-select and multiple import them into separate tracks of an empty Audacity Project.
2) use Audacity 1.3.2 Beta which can export the individual tracks in a Project as one multichannel audio file. So if you had a Project with 6 mono or left/right tracks, it could be exported as a one 6-channel audio file, and any 1.2.x user of Audacity can open that file and see the 6 channels displayed as individual tracks. To use multichannel export you must go to the File Formats tab of Preferences and turn on "Advanced Mixing Options" in the "When exporting tracks" panel.
To export your Project as audio file(s) you use the File > Export as... command. If you export as a .WAV or .AIFF file this enables you to send the file with no loss of audio quality, but the audio file would still take up 10 MB per minute for a stereo file of CD quality (44 100 Hz, 16 bit). However if you export as an .MP3 file you can reduce the size of the exported file considerably. MP3 loses audio quality but still gives you reasonable sound at Audacity's default MP3 export bitrate of 128 kbps, which takes up about 1 MB of space per minute. You can compress the file further at the cost of further quality loss if you reduce the MP3 bitrate on the File Formats tab of Audacity Preferences, at "MP3 Export Setup". Note if you want to export MP3s you need to add the LAME encoder to your computer. Instructions for doing this are at: Lame Installation
Even so, sending files greater than 5 MB by email is usually out of the question due to server bandwidth and storage restrictions. Some webmail services such as GMail do allow files up to 10 MB to be transferred. The solution again is to use a web-based transfer service like yousendit.com, or burn the exported audio file on to an audio CD and send it by snail mail. If you want to burn to an audio CD you need to export 44 100 Hz, 16 bit stereo .WAV or .AIFF files, and tell your burning software to burn an "audio" or "music" CD. These instructions will explain how to do this: http://audacity.sourceforge.net/help/faq?s=files&i=burn-cd
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).