Economics is the main challenge because it's a difficult task and the demand for it is low (market is small if demanding [0]). But the mbrola people, who have

Economics is the main challenge because it's a difficult task and the demand for it is low (market is small if demanding [0]). But the mbrola people, who have a nice free speech synthesis program that also isn't opensource, [1] say it's a hard technical problem too. [0] http://www.ted.com/talks/roger_ebert_remaking_my_voice http://www.ted.com/talks/roger_ebert_remaking_my_voice [1] http://tcts.fpms.ac.be/synthesis/mbrola.html http://tcts.fpms.ac.be/synthesis/mbrola.html