Neural Text-to-Speech Makes Speech Synthesizers Much More Versatile : Alexa Blogs

A text-to-speech system, which converts written text into synthesized speech, is what allows Alexa to respond verbally to requests or commands. Through a service called Amazon Polly, text-to-speech is also a technology that Amazon Web Services offers to its customers. Last year, both Alexa and Polly evolved toward neural-network-based text-to-speech systems, which synthesize speech from scratch, rather than the earlier unit-selection method, which strung together tiny snippets of pre-recorded sounds. In user studies, people tend to find speech produced by neural text-to-speech (NTTS) systems more natural-sounding than speech produced by unit selection. But the real advantage of NTTS is its adaptability, something we demonstrated last year in our work on changing the speaking style ("newscaster" versus "neutral") of an NTTS system.