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Speech Synthesis English FastPitch

Logo for Speech Synthesis English FastPitch
Mel-Spectrogram prediction conditioned on input text with LJSpeech voice.
Latest Version
April 4, 2023
78.54 MB

Speech Synthesis: FastPitch 1.1 Model Card

Model overview

FastPitch 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.

Model architecture

FastPitch is a fully-parallel text-to-speech model based on FastSpeech, conditioned on fundamental frequency contours. The model predicts pitch contours during inference. By altering these predictions, the generated speech can be more expressive, better match the semantic of the utterance, and in the end more engaging to the listener. FastPitch is based on a fully-parallel Transformer architecture, with much higher real-time factor than Tacotron2 for mel-spectrogram synthesis of a typical utterance.



This model is trained on LJSpeech sampled at 22050Hz, and can be used to generate female English voices with an American accent.

How to use this model

FastPitch is intended to be used as the first part of a two stage speech synthesis pipeline. FastPitch 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)


FastPitch paper:


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