Text to speech engines

I’m trying to find a VOIP-capable programmer-friendly platform for making outbound calls based on information from a database.

I want to have a friendly natural-sounding voice to pronounce client names and a say a canned message about their account with a couple of details from their account and forward the call to an operator if they say operator or press zero.

Any text to speech/IVR programs recommended?

Any suggestions/tools/methods/books from the asterisk community?



cepstral is the best at sounding good and has excellent granular control of the speech using SSML


Thanks for the info mudslide567.

I’ve read about Flit, Festival, and heard the live demo of the voices from the cepstral website and from att. The pricing on cepstral is very reasonable, however i didn’t think much of the voices – sounded to computery. Is there any other text to speech engines that work well with asterisk that sound more human?

I work in a call center environment and the text to speech they use sounds awesome, however the price tag is not possible for this project. Willing to spend up to a couple thousand on the text to speech portion of this project.

And other recommendations?


compared to flite / festival, the cepstral voices are great. the voices are actually human and if you use SSML to write your text, you can make extremely human sounding speech. we have done several where it is indistinguishable to the point of people not realizing it was TTS… however, you do need to become a little proficient at SSML. We have had excellent luck with William, David & Carrie voices …

thanks again for the info.