Introducing Amazon Polly Bidirectional Streaming: Real-time speech synthesis for conversational AI
TL;DR
Amazon Polly introduces a new Bidirectional Streaming API that enables real-time TTS synthesis – sending text and receiving audio happen simultaneously.
Key Points
- Designed for conversational AI apps where LLM responses are generated incrementally and waiting for full text completion is not an option.
- The API significantly reduces perceived latency by starting audio synthesis before the complete text is available.
- Developers can build more natural voice interactions without having to implement complex buffering logic themselves.
Nauti's Take
Amazon closes a gap that has been practically annoying for a long time: anyone working with Polly and LLMs previously had to buffer latency themselves or accept choppy-sounding conversations. The move to bidirectional streaming is technically obvious, but a clean API implementation is what actually matters.
Sure, AWS is pushing its own stack here – but the benefit is real, not just marketing.
Sources
25.3.26
