If you like to contribute you can record voice files for your language and send them to me or create a pull request on github. At the moment there are files for english and german. You can find the voice files here. The filenames should speak for themselves. Currently there are 6 voice files per language but I plan to add more in one of the next releases. I recorded the files with my Jolla 1 phone and saved them as WAV. On Ubuntu I use Audacity to edit and cut the files. Personally I really like female voices, maybe you own one or have "access" to one of those