TTS Provider Settings

What You'll Learn

• How to configure TTS Provider settings
• Configuration items for OpenAI / ElevenLabs
• How to manage API keys for TTS (Text-to-Speech)
• How to add TTS providers

Overview

Manages provider settings for TTS (Text-to-Speech). As of April 17, 2026, Studio supports OpenAI and ElevenLabs.

Access Method

1. Log in to Threedive AI Studio
2. Click and expand "Developer Menu" in the sidebar
3. Select TTS Provider Settings

Developer Menu expanded

Settings Screen

TTS Provider Settings screen - Manage API keys for TTS

Default Settings

The system has the following default settings:

• Default TTS AI: OpenAI TTS API (Default)
• Default High-Quality TTS AI (β): ElevenLabs TTS API

On the list screen, you can check the service name and "Edit" button for each provider.

Adding TTS Providers

You can configure additional TTS providers from the "Add TTS Provider" button. In the add dialog, first select the Provider Type.

TTS Provider Add Dialog - OpenAI selected

Common Configuration Items

Name

• Provider identification name
• Set a name that is easy to distinguish on the list screen

Provider Type

• OpenAI
• ElevenLabs

Switch according to the voice synthesis service you use.

OpenAI Configuration Items

When selecting OpenAI, configure the following items:

OpenAI API Key

• Enter your OpenAI API key
• Used for standard voice (TTS) functionality

TTS Model

• Select a model for voice synthesis
• Default as of April 17, 2026 is gpt-4o-mini-tts

Additional Settings (JSON)

• Optional: Specify additional TTS settings in JSON format

Common System Prompt

• A common prompt applied to all AI avatars using this provider
• Can be used for voice style specification, etc.

ElevenLabs Configuration Items

When selecting ElevenLabs, different items are displayed than OpenAI.

TTS Provider Add Dialog - ElevenLabs selected

ElevenLabs API Key

• Enter your ElevenLabs API key
• A link to obtain the API key is displayed in the dialog

TTS Model

• Select a model for voice synthesis
• As of April 17, 2026, the following models were selectable in the UI:
  • eleven_v3
  • eleven_multilingual_v2
  • eleven_turbo_v2_5
  • eleven_flash_v2_5
  • eleven_monolingual_v1

Language Code

• Not specified: Does not send language_code, leaving it to ElevenLabs' default behavior
• Browser language: Matches the user's browser language
• Fixed: Specifies a fixed ISO 639-1 language code
  • Example: ja, en, fr

Additional Settings (JSON)

• Specify ElevenLabs' voice_settings in JSON
• The following keys are indicated in the UI explanation:
  • stability
  • similarity_boost
  • style
  • use_speaker_boost

Common System Prompt

• The input field is disabled when ElevenLabs is selected
• The UI displays "High-quality voice does not use freeform TTS prompts"

Adding Procedure

1. Click the "Add TTS Provider" button
2. Select provider type
3. Enter provider information
   • Name
   • API Key
   • TTS Model
   • Language code if necessary
   • Additional settings (JSON)
   • Common system prompt (OpenAI only)
4. Click the "Save" button

Editing API Keys

You can update API keys from the "Edit" button of existing providers.

Editing Procedure

1. Click the "Edit" button for the provider you want to edit
2. Enter or update the API key
3. Save the settings

Security Caution

• Store API keys securely
• It is recommended to rotate keys regularly
• Delete keys that are no longer needed

Differences Between OpenAI and ElevenLabs

Item	OpenAI	ElevenLabs
API Key Field	OpenAI API Key	ElevenLabs API Key
Representative Model	gpt-4o-mini-tts	eleven_v3, etc.
Language Code	None	Not specified / Browser language / Fixed
Additional Settings	Generic JSON	voice_settings JSON
Common System Prompt	Available	Disabled

Differences from Realtime Voice Conversation

Item	TTS Provider	Realtime Provider
API	OpenAI TTS API / ElevenLabs TTS API	OpenAI Realtime API, etc.
Processing Method	Text-to-speech conversion	Real-time bidirectional communication
Use Case	Voice synthesis	Real-time conversation

Next Steps

• LLM Provider Settings - Configure custom LLM endpoints
• Realtime Provider Settings - Configure providers for Realtime API
• Error Log Guide - Check and debug errors

Support

For questions about TTS Provider Settings, please contact us through "Support Inquiry" in Threedive AI Studio.