Soprano-80M: an 80M Apache 2.0 TTS that claims 2000x real time on GPU
Soprano-80M is a tiny English-only TTS with under 15 ms streaming latency on GPU, no cloning, Apache 2.0; superseded by Soprano 1.1.
Tagged low-latency
Microsoft releases VibeVoice-Realtime-0.5B, a streaming TTS model under MIT
A single-speaker streaming TTS model that starts speaking in about 300 ms; MIT licensed, but the card says research use only.
Resemble AI releases Chatterbox-Turbo, a 350M MIT TTS built for voice agents
Chatterbox-Turbo is a 350M English TTS with paralinguistic tags, one-step decoding and voice cloning; MIT licensed and watermarked.