# Speech-to-Speech (Amazon Nova 2 Sonic)
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Amazon Nova 2 Sonic enables real-time conversational AI with speech input and output. The following section covers advanced capabilities for building interactive voice assistants, customer service automation, and conversational applications.

## Key features
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Amazon Nova 2 Sonic provides the following capabilities:
+ State-of-the-art streaming speech understanding with bidirectional streaming API that enables real-time, low-latency multi-turn conversations.
+ Multilingual support with automatic language detection and switching. Expressive voices are offered, including both masculine-sounding and feminine-sounding voices, in the following languages:
  + English (US, UK, India, Australia)
  + French
  + Italian
  + German
  + Spanish
  + Portuguese
  + Hindi
+ Polyglot voices that can speak any of the supported languages to enable a consistent user experience even when the user switches languages within the same session.
+ Robustness to background noise for real world deployment scenarios.
+ Robustness to different accents for supported languages.
+ Natural, human-like conversational AI experiences with contextual richness across all supported languages.
+ Adaptive speech response that dynamically adjusts delivery based on the prosody of the input speech.
+ Intelligent turn-taking that detects when users finish speaking and when the assistant should respond, creating natural dialogue rhythm.
+ Graceful handling of user interruptions without dropping conversational context.
+ Knowledge grounding with enterprise data using Retrieval Augmented Generation (RAG).
+ Function calling and agentic workflow support for building complex AI applications.
+ Asynchronous tool handling that executes tool calls while maintaining conversation flow, allowing the assistant to continue speaking while tools process in the background.
+ Cross-modal input support for both audio and text inputs within the same conversation, enabling flexible interaction patterns.
+ Connection limit of 8 minutes, with connection renewal and session continuation pattern available in code samples.