New answers tagged software
You are looking for Mbrola! It's an open-source, text-based diphone synthesizer. While it doesn't allow you to control subtle information like formant frequency, it's perfect for controlling pitch and duration. The one caveat is that I have yet to get it to work on an Intel-based Mac, but that is primarily because the Windows GUI works so well that I could ...
Praat is free and has been cited in many publications. It's the de facto standard for creating phonetic stimuli.
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