The OpenAI model to use for speech creation (e.g., 'tts-1' or 'tts-1-hd').
Optional
responseThe format of the audio output; defaults to 'mp3'.
Optional
speedThe speed of the speech; defaults to 1.0.
Optional
voiceThe voice to use for speech synthesis; defaults to model-specific value.
Options for creating speech using OpenAI's text-to-speech models.