I use TTS to tell me the time every 30 minutes.
I have used SVOX offical application for a year, but it has since stopped working, due to not being able to download the voices onto my new smartphone.
So, I searched for a new alternative and found this application.
https://play.google.com/store/apps/details?id=es.codefactory.vocalizertts
The application is free, but then you need to buy each voice separately.
Two voices in my language (Portuguese from Portugal) are similar to those in SVOX, but they added one more.
To answer your question:
Go to:
Settings -> Additional settings -> Language and input -> Text to speach (TTS) -> change the following fields:
1) Under your TTS of choice, choose the dented wheel (settings) on the right hand side;
Choose your options accordingly, like your language of choice and your voice of choice.
2) Go to the last option on the TTS menu, something like "Predefined language status";
Choose your voice of choice.
3) Select "Listen to a sample";
Is it working?
Hope this works for you!