Hume Text-to-Speech

Overview

Hume provides expressive text-to-speech synthesis using their Octave models, which adapt pronunciation, pitch, speed, and emotional style based on context. HumeTTSService offers real-time streaming with word-level timestamps, custom voice support, and advanced synthesis controls including acting instructions, speed adjustment, and trailing silence configuration.

Hume TTS API Reference

Pipecat’s API methods for Hume TTS integration

Example Implementation

Complete example with word timestamps and interruption handling

Hume Documentation

Official Hume TTS API documentation and features

Voice Library

Browse and manage available voices

Installation

To use Hume services, install the required dependencies:

uv add "pipecat-ai[hume]"

Prerequisites

Hume Account Setup

Before using Hume TTS services, you need:

Hume Account: Sign up at Hume AI
API Key: Generate an API key from your account dashboard
Voice Selection: Choose voice IDs from the voice library or create custom voices

Required Environment Variables

HUME_API_KEY: Your Hume API key for authentication

Configuration

HumeTTSService

str

default:"None"

Hume API key. If omitted, reads the HUME_API_KEY environment variable. Raises ValueError when neither is set.

str

default:"None"

deprecated

Deprecated since 0.0.105, removed in 2.0.0. Use settings=HumeTTSService.Settings(...) instead.

int | None

default:"48000"

Sample rate the output frames are labeled with. Hume always streams 48 kHz audio and the service doesn’t resample it, so any other value logs a warning and the audio plays at the wrong speed.

InputParams

default:"None"

deprecated

Deprecated since 0.0.105, removed in 2.0.0. Use settings=HumeTTSService.Settings(...) instead.

HumeTTSService.Settings

default:"None"

Runtime-configurable settings. See Settings below.

Settings

Runtime-configurable settings passed via the settings constructor argument using HumeTTSService.Settings(...). These can be updated mid-conversation with TTSUpdateSettingsFrame. See Service Settings for details.

Parameter	Type	Default	Description
`model`	`str`	`None`	Not sent by this service; reported only as the model name in metrics and traces. (Inherited.)
`voice`	`str`	`None`	Hume voice ID; voice names aren’t supported. Required: while it’s `None`, each request pushes an `ErrorFrame`. (Inherited.)
`language`	`Language \| str`	`None`	Language used to split text into sentences; not sent to Hume. (Inherited.)
`description`	`str`	`None`	Description to guide voice synthesis.
`speed`	`float`	`None`	Speech rate control.
`trailing_silence`	`float`	`None`	Trailing silence duration in seconds.
`temperature`	`float`	`None`	Sampling temperature for speech generation. Higher values increase variation, lower values increase consistency.

Usage

Basic Setup

import os

from pipecat.services.hume.tts import HumeTTSService

tts = HumeTTSService(
    api_key=os.getenv("HUME_API_KEY"),
    settings=HumeTTSService.Settings(
        voice="your-voice-id",
    ),
)

With Acting Directions

tts = HumeTTSService(
    api_key=os.getenv("HUME_API_KEY"),
    settings=HumeTTSService.Settings(
        voice="your-voice-id",
        description="Speak warmly and reassuringly",
        speed=1.1,
        trailing_silence=0.5,
    ),
)

Updating Settings at Runtime

Voice and synthesis parameters can be changed mid-conversation using TTSUpdateSettingsFrame:

from pipecat.frames.frames import TTSUpdateSettingsFrame
from pipecat.services.hume.tts import HumeTTSSettings

await worker.queue_frame(
    TTSUpdateSettingsFrame(
        delta=HumeTTSSettings(
            speed=1.3,
            description="Speak with excitement",
        )
    )
)

Notes

Word timestamps: The service provides word-level timestamps for synchronized text display. Timestamps are tracked cumulatively across utterances within a turn.
Description versions: When description is provided, the service uses Hume API version "1". Without a description, it uses the newer version "2".
Audio buffering: Audio is buffered internally until a minimum chunk size is reached before being pushed as frames, reducing audio glitches.

Get Started

Pipecat Server

Client SDKs

Pipecat Flows

Pipecat Cloud

CLI

Pipecat Context Hub

Hume Text-to-Speech

Overview

Hume TTS API Reference

Example Implementation

Hume Documentation

Voice Library

Installation

Prerequisites

Hume Account Setup

Required Environment Variables

Configuration

HumeTTSService

Settings

Usage

Basic Setup

With Acting Directions

Updating Settings at Runtime

Notes

​Overview

Hume TTS API Reference

Example Implementation

Hume Documentation

Voice Library

​Installation

​Prerequisites

​Hume Account Setup

​Required Environment Variables

​Configuration

​HumeTTSService

​Settings

​Usage

​Basic Setup

​With Acting Directions

​Updating Settings at Runtime

​Notes

Overview

Installation

Prerequisites

Hume Account Setup

Required Environment Variables

Configuration

HumeTTSService

Settings

Usage

Basic Setup

With Acting Directions

Updating Settings at Runtime

Notes