Voice Preview

Use the Voice Preview feature to quickly test voice output.

Updated in 2026.11

The Voice Preview feature lets users quickly test their AI Agents’ voice output in the Flow editor or Interaction Panel without going through the entire Flow with a mock call. This feature supports cloud speech-to-text (STT) and text-to-speech (TTS) services. To use the Voice Preview, you need to enter text or SSML syntax, and select the language and voice.

Prerequisites

• To activate access to speech provider credentials from Voice Gateway in the Voice Preview section in the Project settings, do the following:
  • For on-premises installations, set FEATURE_VG_SPEECH_CREDENTIAL_SOURCE: "true" in values.yaml.
  • For Cognigy SaaS installations, contact Cognigy technical support.

Restrictions

• The Voice Preview feature supports only the Google, Microsoft, Amazon AWS, Deepgram, and Speechmatics speech providers. When testing a voice Flow through the Interaction Panel, you must check the STT and TTS settings of the voice Nodes to ensure that one of these providers is specified. If any other provider, such as ElevenLabs, is specified in the Nodes, the Interaction Panel won’t support the voice conversation.
• To use SSML syntax in the Voice Preview, the speech provider must support SSML syntax. For example, ElevenLabs doesn’t support SSML. Check the documentation of your speech provider to see if it supports SSML.

Access STT and TTS Providers

If your environment has network connection restrictions or requires strict security rules, make sure that both STT and TTS providers are accessible. Add the IP address ranges of your STT and TTS providers to the firewall’s whitelist. This approach ensures the Cognigy.AI server can interact smoothly with both providers, guaranteeing the expected functionality of the Voice Preview feature.

The Voice Preview section includes a message that indicates which tab configuration is in use.

How to Use Voice Preview

Configure Speech Provider

To configure a speech provider, you can either set it up in Cognigy.AI or select one from Voice Gateway.

Set Up Speech Provider in Cognigy.AI

Depending on whether you have access to Voice Gateway speech credentials or only to Cognigy.AI speech credentials from the Project settings, set up the speech provider as follows:

With Voice Gateway Speech Credentials

1. In the left-side menu of the Project, go to Manage > Settings.
2. Go to the Local Credentials tab in the Voice Preview Settings section and select one of the following providers from the Speech Provider list:

Only Cognigy.AI Speech Credentials

1. In the left-side menu of the Project, go to Manage > Settings.
2. Go to the Voice Preview Settings section and select one of the following providers from the Speech Provider list:

Microsoft

1. Next to the Speech Connection field, click to enter credentials.
   
2. In the New Connection window, fill in the following fields:
   
   • Connection — specify a unique connection name.
     
   • API Key — specify an API key for Microsoft Azure Speech Services. Log in to the Azure portal, navigate to your Speech Services resource, and copy the API key labeled as Key1 from the Keys and Endpoint section. For more information, read the Microsoft Azure AI documentation.
     
   • Region — this parameter is optional. Enter a specific region if necessary. The supported voices vary by region. Verify which voices are available in the provided region in the Azure AI Speech regions documentation.

Google

1. Next to the Speech Connection field, click to enter credentials.
   
2. In the New Connection window, specify a unique name for your connection in the Connection field.
   
3. Click Upload JSON File and upload the JSON file that you received from Google Speech Services. To obtain a JSON key file for accessing Google Speech Services, first create a service account in the Google Cloud Console under IAM & Admin. Assign the appropriate roles, generate a JSON key file for the service account, and download this key.
   

Amazon

1. Next to the Speech Connection field, click to enter credentials.
   
2. In the New Connection window, fill in the following fields:
   
   • Access Key ID — specify an Access Key ID. Log in to the AWS Management Console, go to the IAM dashboard, select Users, and choose the IAM user. Navigate to the Security credentials tab, and under Access keys, create a new access key if one hasn’t been created. Copy the Access Key ID provided after creation.
     
   • Secret Access Key — specify a Secret Access Key. After creating the access key, you’ll be prompted to download a file containing the Access Key ID and the Secret Access Key. Alternatively, you can retrieve the Secret Access Key by navigating to the IAM dashboard, selecting the user, going to the Security credentials tab, and clicking Show next to the Access Key ID to reveal and copy the Secret Access Key.
     
   • Session Token — this parameter is optional. If you use temporary security credentials, obtain the token when using AWS STS (Security Token Service) to assume a role or federate users.
     
   • Region — this parameter is optional. Enter the AWS region where your Amazon Polly resources are located, for example, us-east-1 for the US East (N. Virginia) region.
     

Deepgram

1. Next to the Speech Connection field, click to enter credentials.
2. In the New Connection window, fill in the following fields:
   • Connection — specify a unique connection name.
   • API Key — specify an API key for Deepgram. To obtain the API key, log in to the Deepgram Console, navigate to the Settings of your Deepgram Project, and select API Keys. For more information, read the Deepgram documentation.

ElevenLabs

The feature is hidden behind a feature flag. Activate ElevenLabs Speech Services on the Cognigy.AI side:

• If you have a SaaS installation, contact Cognigy technical support.
• If you have an on-premises installation, specify FEATURE_ENABLE_ELEVENLABS_STT_VENDOR=true in values.yaml.

1. Next to the Speech Connection field, click to enter credentials.
2. In the New Connection window, fill in the following fields:
   • Connection — specify a unique connection name.
   • API Key — specify an API key for ElevenLabs. To get the API key, log in to the ElevenLabs platform, navigate to your account settings, and find the API key section. For more information, read the ElevenLabs documentation.
   • Region — select one of the following regions:
     • Global — for all global ElevenLabs services.
     • EU — for ElevenLabs services hosted in the European Union.
   • TTS model — select the TTS model to use for text-to-speech conversion.
   • STT model — select the STT model to use for speech-to-text conversion.

Speechmatics

Support for Speechmatics is hidden behind a feature flag. To activate Speechmatics:

• For SaaS installations, contact Cognigy technical support.
• For on-premises installations, specify the feature flags in values.yaml.

1. Next to the Speech Connection field, click to enter credentials.
2. In the New Connection window, fill in the following fields:
   • Connection — specify a unique connection name.
   • API Key — specify an API key for Speechmatics. For more information on Speechmatics API keys, read the Speechmatics Authentication guide.
   • Region — select one of the following regions to host the data processed by Speechmatics:
     • EU (EU2 - On Demand) — points to the on-demand endpoint for Speechmatics services located in the EU.
     • EU (EU1 - Enterprise) — points to the enterprise endpoint for Speechmatics services located in the EU.
     • US (US1 - Enterprise) — points to the enterprise endpoint for Speechmatics services located in the U.S.

3. Click Create.
4. To check the connection, click Test.

You can set up multiple speech providers. By default, the speech provider selected in the Speech Provider list is applied to your Flows and the Interaction Panel. You can change the voice and speech provider for your AI Agent, for example, in the AI Agent Node or Set Session Config Node without switching the default speech provider.

Select Speech Provider from Voice Gateway

This feature is in beta. We encourage you to try it out and provide us with feedback.

1. In the navigation menu, go to Manage > Settings.
2. On the Voice Gateway tab in the Voice Preview Settings section, configure the following:

• Synthesizer (Text-to-Speech) — select the speech provider for TTS.
• Recognizer (Speech-to-Text) — select the speech provider for STT.

Use Voice Preview

You can access the Voice Preview feature in two different ways:

• In the Flow editor, click .
• In the Interaction Panel, hover over the AI Agent message in the chat and click in the interactive tooltip. The Voice Preview button is displayed only for certain types of output, including regular text output, fallback text, and text or SSML output from channels that support voice.

More Information

• Interaction Panel
• Voice Gateway
• Voice Nodes