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CatalogModelsRIVA EnglishUS RADTTS


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Riva multisepaker with IPA for G2P



Latest Version



February 27, 2023


419.48 MB

Speech Synthesis: RADTTS Model Card

Model overview

RADTTS is a mel-spectrogram generator, designed to be used as the first part of a neural text-to-speech system in conjunction with a neural vocoder. This model uses the International Phonetic Alphabet (IPA) for inference and training instead of ARPABET.

Model architecture

RADTTS is a parallel flow-based generative network for text-to-speech synthesis. It extends prior parallel approaches by additionally modeling speech rhythm as a separate generative distribution to facilitate variable token duration during inference.



This model is trained on a proprietary dataset sampled at 44100Hz, and can be used to generate English voices with an American accent. This model supports 1 male voice and 1 female voice.

How to use this model

RADTTS is intended to be used as the first part of a two stage speech synthesis pipeline. RADTTS takes text and produces a mel spectrogram. The second stage takes the generated mel spectrogram and returns audio.


English text strings


Mel spectrogram of shape (batch x mel_channels x time)


RADTTS paper:


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