Pass this command a process string array to be filled with all the available TTS voices on your machine, in the order they have been loaded. Note that the array should not be sorted when presented to the user, as the original index order is used when setting the voice (below).

NOTE: If you elect to use the Cepstral engine, then only Cepstral voices are loaded, without the preceeding "Cepstral" in the name.