If you use OS X Mail, as with most e-mail clients you will hear a small new mail notification sound when you receive new messages. If you do not like the default sound that is configured for Mail, then you can change it. Not only can you change to use one of Apple’s built-in sounds, but you can use any sound bite you want.

To change the default sound, you simply go to the General section of Mail’s preferences, where you will see a drop-down menu for selecting the New Mail sound. When doing this, you have three options for choosing sounds from this menu. The first is to simply use on of the built-in system sounds that are listed, but these may be a bit boring and you might want something different.

If you have a custom sound that you would like to add to this menu, then you can do so in two ways. The first and easiest is to choose the option to add/remove custom sounds, and then select a sound to use from your Mac’s hard drive. The sound can be any .aif, .wav, .mp3, or .m4a, or similarly supported audio format; however, be sure the sound is not too long in length (ie, 2 seconds or less is a good idea). If you choose an entire recording of Beethoven’s 9th symphony, then whenever you receive a new message, you will have an hour or so of music to listen to.

You can use a number of different audio programs for cutting out a 1-2 second chunk of an mp3 or other audio file for use as a system sound. One of these is Audacity, or you can use QuickTime 7 (May require QuickTime 7 Pro), but there are plenty of other options you can choose from. In most programs, you will drag a couple of sliders along the sound’s timeline to select your desired section, and then crop and save it as a new file.

The second way to add sounds to this menu are to add them to a folder called Sounds in the global library, or in your user library. To do this, go to Macintosh HD > Library, and then open or create a folder called Sounds. In here, simply add your desired .aif, .m4a, .wav, or .mp3 files, and they will now be available in Mail’s New Mail sound menu.

Adding these files to the global library folder in this way will make them available to all users, so if you want sounds to be for your account only, then you can add them to the same folder in your user account’s library. To access this library, hold the Option key and choose “Library” from the Go menu in the Finder. In here, similarly create or open the Sounds directory, and then add your files to it.

Finally, while Apple’s New Mail sound can be useful, it is not conditional and will sound for most new messages that your Mac receives. An alternative to this is to set this menu to No Sound, and then have Mail play sounds for individual accounts via rules. To do this, go to the Rules section of Mail’s preferences, and then create a new rule. Then set the condition for the rule to run if “any” condition is met, and set the condition to be the “Account” is one of your desired accounts. You can add more than one account here to assign the same sound to these accounts as well. Then set the “Perform the following actions” section to “Play Sound” and then select your desired sound from the secondary menu.

With this rule set up, this sound will play whenever messages are received in these accounts. You can then set up additional rules for your other accounts, so you can assign different sounds to them.

Have any tips for managing new mail sounds in OS X? If so, then share them in the comments!