With new advances in TTS technologies coming out from Google, Alexa’s voice is started to sound a bit dated and choppy. Tacotron2 and Wavenet have created more dynamic, emotional and cheerful voices that are more tolerable to listen to for longer amounts of information.
Google, of course, has more years of R&D to support it’s TTS work. Likewise, Amazon doesn’t shy down to major challenges and seeing how Alexa can speak multiple languages, is likely working on the next generation of the Alexa voice.
To get to ubiquity and go from robot assistant to true personality, these voices need to be indiscernible from human speech. Once we get to that level, we’ll start to get confused about the realness of Alexa/Google Assistant. That’s when the true power of these assistants will come forward.