> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> STT). 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.

# Speko

> Use Smallest AI's Lightning v3.1 and Pulse as the TTS and STT stages in Speko's voice agents.

[Speko](https://speko.ai) is a voice agent platform for building, evaluating, and monitoring voice agents. Speko lets you configure your TTS and STT stages independently in **Cascaded** mode - pick [Smallest AI](https://smallest.ai)'s Lightning v3.1 for voice output, Pulse for speech-to-text, or both.

## Prerequisites

* A [Speko](https://speko.ai) account
* Access to your agent's Models configuration in the Speko dashboard

---

## Setup

#### Create a Speko account

Sign up at [speko.ai](https://speko.ai) if you don't already have an account.

#### Open the Models tab

In Speko, open the **Models** tab for your agent and choose **Cascaded** mode with the Advanced model setup.

#### Set the TTS and/or STT stage

In **Cascaded Stages**:

* Set the **Voice (TTS)** stage to **Lightning v3.1, Smallest AI Lightning TTS** for speech output.
* Set the **STT (Speech-to-Text)** stage to **Pulse, Smallest AI Pulse STT** for transcription.

You can configure one or both stages with Smallest AI.

#### Save and verify

Save and run your agent, then verify it in Speko's Evaluation suite with reliability checks and live monitoring.

---

## Notes

* Speko benchmarks Pulse as its fastest streaming STT option, which keeps end-of-turn latency - the wait between a caller finishing and the agent replying - low.
* Speko lists Lightning v3.1 (`smallest:lightning_v3.1`) in its TTS model benchmarks for naturalness and synthesis latency, including English, German, and French.
* See [Speko's Pulse STT benchmark](https://benchmarks.speko.ai/stt/smallest-ai-pulse) and [Speko's Lightning v3.1 TTS benchmark](https://benchmarks.speko.ai/tts/smallest-lightning-v3-1) for latency and quality numbers.

## Links

#### [Speko](https://speko.ai)

Build, evaluate, and monitor voice agents

#### [Speko Documentation](https://docs.speko.dev)

Full Speko platform documentation

#### [Lightning v3.1 Overview](/models/text-to-speech/overview)

Supported voices, languages, and streaming

#### [Pulse STT Overview](/models/speech-to-text/overview)

Supported languages, features, and limits

> Use Smallest AI's Lightning v3.1 and Pulse as the TTS and STT stages in Speko's voice agents.