NVIDIA Releases NemotronLabs VoiceChat 11B: An Open Full-Duplex Speech-to-Speech Model with ~450 ms Turn-Taking and Live Tool Calling

NVIDIA has released NemotronLabs VoiceChat 11B , an open 11B end-to-end speech-to-speech model for real-time, full-duplex conversation. Instead of chaining ASR, an LLM, and TTS, it performs streaming speech understanding and speech generation in one unified network. That removes the multi-model orchestration and API handoffs a cascaded stack requires, and cuts end-to-end latency: measured smooth turn-taking latency is 448 ms on Full-Duplex-Bench 1.0 . The model listens while it speaks, so a user can barge in mid-turn and the agent yields, with a take-over rate of 1.00 at 480 ms. It is also first open full-duplex model to support tool calling while conversation keeps flowing, using a separate output channel for <TOOLCALL> scripts along with operator-defined “on-hold” lines that fill the gap while an API runs.