Admin Guides Interactive Voice Response (IVR) Using the Contact Flow Engine Understanding Modules Current: Speak PDF Download PDF Download page Speak. Current page All pages Speak Use the Speak module to generate TTS (text-to-speech) prompts to the caller as configured from within the IVR. This module requires Advanced TTS, a billable feature that must be active on your portal to speak TTS messages. For more information, see Billing Tab. Message PropertiesMessage PropertiesDefinitionText to speakDefine text that must be converted to speech.TTS EngineSelect among available Text-To-Speech Engines that will provide the speech. ConnectorsFor information on the module connectors, see Understanding Connectors. ×