Festival is a speech synthesis system. It can be found at http://www.cstr.ed.ac.uk/projects/festival/ or http://www.speech.cs.cmu.edu/festival/ .
Festival is used as the speech synthesizer for Festtcl and TkFestival [1 ]
The Festival distribution includes several voices in English (American and British accents). Other voices for English, Spanish, French, German, etc. can be found at:
Also see: CSLU Toolkit, Rsynth, Speech Synthesis, or Talk to me Tcl