Linux/espeak

Female voice
espeak -ven-us+f5 -s120 "test"

"Use the -v option to specifiy a voice. After that you can provide the type of language, such as en or en-us. After that, add a plus, then either m or f, and a 1 – 5. The s option lets you set the speed. Unfortunately, most of the voices sound pretty bad"

Ref:

Fix Alsa warnings
Edit /usr/share/alsa/alsa.conf pcm.front cards.pcm.default
 * 1) pcm.front cards.pcm.front

sudo apt-get --no-install-recommends install jackd2 jackd -d alsa

jackd -d dummy 2>/dev/null 1>/dev/null &

jackd -p 8 -r -m -d dummy > /dev/null 2>&1

Ref: