Mac2Speech - a Speech Synthesis Server for OS X, allowing you to use your Mac as a Text-To-Speech server, converting text strings into MP3 voice sound files on the fly.
A web user-interface allows for rapid experimentation with different languages and voices.
Sending an HTTP GET with voice and text parameters, will result in audio content is streamed directly in the HTTP response.
If an optional save=true parameter-value pair is sent with the request, an additional HTTP header gets include, to encourage downloading instead of directly playing the MP3.
Sending an HTTP POST with voice and text parameters, will create and temporarily store an MP3 file on the server.
The Web user-interface allows access to all installed voices and the HTTP service supports all installed voices. Neither of the pre-installed voices are great, but Apple provides access to higher quality voices, if you care enough to install them. ‘Allison’ for instance is great and less robotic, but there is still room for improvement.
To install some of the better voices from Apple, open ‘System Preferences’ and ‘Dictation & Speech’. Now click on the ‘Text to Speech’ and then on the selected ‘System Voice’ (e.g. Alex) and in the appearing drop-down, select Customize...
Here you can discover (play) and install some amazingly good voices. Please do yourself a favor and install Allison and Tom, two very good American-English voices.
Not only are mp3 files almost universally playable, they are also considerably smaller than wav or aiff files for instance, and still provide a decent sound quality. Mac2Speech comes with LAME built-in. LAME is a high quality MPEG Audio Layer III (MP3) encoder licensed under the LGPL.