and diverse samples whose distribution is close to the training data. Among them, the FM duration
model creates more varying speaking styles compared to the regression one which ASR may struggle
more to recognize. Voicebox even yields lower FSDs than the real samples from the Librispeech
test-other split, because the latter contains only tens of speakers and the diversity is limited.
We next train an ASR model using only synthetic speech and evaluate it on real speech, which
has not been successful before because synthetic data were not realistic and representative enough.
Voicebox-Text-GuidedMultilingual UniversalSpeechGenerationatScale