Jump to this page, scroll down almost all the way to the bottom, then click the various play buttons to hear how Siri’s voice has changed with each new major iOS release.
To my ear, each rev gets higher in pitch, with the iOS 11 version of Siri sounding like a different person entirely than the Susan Bennett voiced Siri we came to know and love.
The iOS 10 version of Siri is a recognizable voice to me, as recognizable as a friend’s voice. The new version sounds a bit impersonal.
From the text above the samples:
For iOS 11, we chose a new female voice talent with the goal of improving the naturalness, personality, and expressivity of Siri’s voice. We evaluated hundreds of candidates before choosing the best one. Then, we recorded over 20 hours of speech and built a new TTS voice using the new deep learning based TTS technology. As a result, the new US English Siri voice sounds better than ever.
I expect the new version is an early wave of the latest voice generation approach used by Apple and that I will get used to this new voice over time.