Install the AUR package.
Packages named mbrola-voices-xxx are available in the AUR
Once you have installed the wanted voice(s) go to the directory of the installed language:
$ cd /usr/share/mbrola/us1/
then list the test files:
$ ls TEST/
If there are no test files for this language, try with another language or skip to #Install a text-to-phonemes program.
Else choose a test file (files with .pho extension) and try:
$ mbrola ./us1 ./TEST/mbrola.pho ~/test.wav; aplay ~/test.wav; rm ~/test.wav
If the installation worked ok, you should hear the voice now.
Note that we this test did not give a text file to mbrola but a phoneme file. To make it a text-to-speech system, see below.
Install a text-to-phonemes program
To obtain a full TTS system we need a text-to-phonemes program compatible with mbrola: List of TTS programs compatible with mbrola.