Grad-TTS

by Huawei Noah's Ark Lab

Diffusion-probabilistic TTS reference implementation.

TL;DR

Diffusion-probabilistic TTS reference implementation.

Best for researchers exploring diffusion-based TTS architectures. Pricing: free (MIT).

Category
Open source
License
—
Stars
—
Last push
—
Pricing
free (MIT)
Platforms
Linux

What it is

Grad-TTS is Huawei Noah's Ark Lab's diffusion-based TTS, one of the first applications of diffusion to speech synthesis. Demonstrates the lineage that StyleTTS 2 and F5-TTS extend. MIT. Consent posture: synthetic-only.

Best for: Researchers exploring diffusion-based TTS architectures.
Watch out for: Research-grade; sampling can be slow without distillation.

Install / use

git clone https://github.com/huawei-noah/Speech-Backbones

Features

Speaker diarizationNo
Word-level timestampsNo
Streaming / real-timeNo
Languages supported1
HIPAA eligibleNo

Grad-TTS vs Whipscribe

FeatureGrad-TTSWhipscribe
CategoryOpen sourceTranscription APIs
Pricingfree (MIT)free beta
Speaker diarization—Yes
Word timestamps—Yes
Streaming—No
Languages199
PlatformsLinuxWeb, API, MCP

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