https://techcrunch.com/2018/05/16/alexa-developers-get-8-free-voices-to-use-in-skills-courtesy-of-amazon-polly/

Now Alexa’s voice apps don’t have to sound like Alexa. Amazon today is offering a way for developers to give their voice apps a unique character with the launch of eight free voices to use in skills, courtesy of the Amazon Polly service. The voices are only available in U.S. English, and include a mix of both male and female, according to Amazon Polly’s website.

Amazon Polly was first introduced at Amazon’s re:Invent developer event in November 2016, and has been steadily ramping up its capabilities in the time since. The text-to-speech service today is capable of things like whispering, speech marks, using a timbre effect, and dynamic range compression – all which make the voices sound more natural.