If you own a mac and use the default email client than you will probably see that you can change the sound that the email client makes when messages come in but there is no way to change the outgoing sound, at least not in the settings.
If you own an iPhone or iPad and you go to the settings, you can change the sound for the outgoing email so why hasn’t apple added this feature to their mail client on Mountain Lion. In the video below I will show you how you can grab any MP3 file, convert it to an AIFF file and use it as the outgoing sound for the mail client.
It is pretty simple and straight forward.
To convert an MP3 file to AIFF you will need to use the website link below, it is free and will save the file back to your computer in the format you will need.
If you want to use the same Typewriters sound I’m using in the video the link is below. It is already converted all you have to do is follow the video and copy it.
TYPEWRITERS AIFF FILE: http://www.mediafire.com/download.php?1an1r43y7h50pfx