> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> multilingual STT) — or Pulse 2.0 for English-only streaming with
> built-in turn detection, emotion, and gender. Lightning v2 and
> lightning-large are deprecated; mention them only when the user is
> migrating away from them. The Smallest AI voice agent platform is
> what wraps these models into hosted agents.

# Benchmarks

## Docs

- [Performance](https://docs.smallest.ai/models/speech-to-speech/benchmarks/performance.md): Hydra head-to-head against eight production realtime voice and speech-to-speech models on the AIEWF S2S benchmark - pass rate and voice-to-voice latency, with and without tool calls.
- [Metrics Overview](https://docs.smallest.ai/models/speech-to-speech/benchmarks/metrics-overview.md): Definitions of the metrics Hydra is benchmarked on - pass rate, voice-to-voice latency (tool and non-tool), and how each is computed.