ChatTTS vs Google Flow Music (formerly Riffusion)

ChatTTS is an open-source text-to-speech model built for dialogue. The 2Noise team trained it on over 100,000 hours of Chinese and English speech so it sounds natural in back-and-forth conversation, not just scripted narration.

What sets it apart is prosody control at a granular level. The model can layer in laughter, pauses, and interjections, and it handles multiple speakers in a single session. That makes it a fit for LLM assistants, conversational audio, and dialogue-heavy multimedia.

Developers install it via pip or clone the GitHub repo. The open-source release on Hugging Face is a 40,000-hour base model under AGPLv3+. The team positions it for research and dialogue use cases, with contact at [email protected] for roadmap questions.

Google Flow Music lets you create full-length songs, remix tracks, and publish music through a conversational studio built on Google's Lyria 3.5 model. riffusion.com now redirects to flowmusic.app, where you chat with Producer like you are in a session, iterate on vocals and arrangement, and export finished tracks.

Unlike one-shot music generators that spit out a clip and stop, Flow Music focuses on iterative editing. Replace and Extend let you swap specific sections or continue a song past its endpoint without regenerating the whole track. You can also direct Veo-powered music videos, split stems, apply audio effects, and vibe-code custom instruments or mini apps inside Spaces.

The free tier includes daily top-up credits and two concurrent generations with no credit card required. Paid plans raise monthly credits, concurrent generation limits, and add member perks. Google acquired the Riffusion team in 2026 and folded the product into Google Labs alongside Lyria and Veo.