Voice Providers
Priya calls Acme Diagnostics and wants to speak Hindi. Asha, the admin, wants that call to sound natural, answer in the right language and respond quickly. This page covers every voice option the Studio offers today, so you can pick the one that fits your language, speed and budget.
You set voice on the agent's AI Model sub-node, in the Voice agent model section. The same choice applies to browser voice and phone calls. You don't need a provider account: every model below works as soon as you pick it, and its usage is charged to your credits.
Two modes
| Mode | What happens | When to choose it |
|---|---|---|
| Live — one speech-to-speech model | One model listens and speaks directly | The most natural turn-taking and the lowest delay |
| Pipeline — speech-to-text → LLM → text-to-speech | One model transcribes, a chat model thinks, and a voice model speaks | Indian-language voices, or when you want to choose the brain yourself |
Every model row also offers Platform default, which uses Perfox's recommended model.
Live models and voices
| Model | Voices |
|---|---|
| Gemini 3.8 Live, Gemini 3.8 Live (extended thinking) | 30 Gemini voices. The default is Aoede. The list shows gender where it's known: for example Aoede, Kore, Leda, Despina and Achernar are female, and Charon, Puck, Orus, Fenrir and Zephyr are male |
| OpenAI Realtime, OpenAI Realtime 2.1, OpenAI Realtime 2.1 Mini | alloy, ash, ballad, coral, echo, sage, shimmer, verse, marin, cedar. The default is marin |
Pipeline models and voices
| Step | Options |
|---|---|
| Speech-to-text | Sarvam Saaras v3, or ElevenLabs Scribe v2 Realtime |
| Voice brain | Any chat model: Gemini 3.7 Flash, Gemini 3.6 Flash, Gemini 3.5 Flash, Gemini 3.5 Flash Lite, Gemini 3.1 Flash Lite, Gemini 2.5 Flash, Gemini 2.5 Flash Lite, GPT-4o, GPT-4o Mini, Sarvam 105B, GPT-OSS 120B (Groq). It also has Creativity and Max reply length settings |
| Text-to-speech | Sarvam Bulbul v3: 38 Indian voices, male (Shubh, Aditya, Rahul, Kabir…) and female (Ritu, Priya, Neha, Kavya…). ElevenLabs Flash v2.5: Sarah, Laura, Alice, Matilda, Jessica and Bella (female), and George, Roger, Charlie, Callum, Liam, Will, Eric and Harry (male) |
The Voice list only offers voices the selected speaking model actually has, so you can't pick a voice from another vendor by mistake.
The agent's gender
The voice you pick also sets how the agent refers to itself, which matters in languages with gendered grammar (Hindi "सकता" vs "सकती"). This carries over to WhatsApp, email and web chat, where there's no voice. A line under the voice confirms it, for example "Agent refers to itself as female, from this voice."
If the voice doesn't tell Perfox a gender (OpenAI voices), or the agent doesn't speak at all, a How the agent refers to itself → Gender control appears instead: Not set, Female, Male or Non-binary.
Pick a voice explicitly if gender matters, rather than leaving it on Default: each vendor's default voice has its own gender (Sarvam's default Shubh is male, Gemini's default Aoede is female).
While the caller waits
Under the voice settings, While the caller waits chooses what the caller hears in three situations. For each one you can pick Silence or a Periodic tone. A spoken option is shown as coming soon.
| Situation | Default |
|---|---|
| AI looking up (the agent is running a tool) | Silence |
| Operator hold (a person has put the caller on hold, or a transfer is ringing) | Periodic tone |
| Waiting for operator (an inbound caller is waiting for an operator to answer) | Silence |
A call from start to finish
Setup. Asha opens the AI Model sub-node for the Acme support agent and picks Pipeline, with Sarvam Saaras v3 speech-to-text and Sarvam Bulbul v3 text-to-speech. She picks the Ritu (female) voice and sets the Personality to answer in Hindi.
Action. Priya calls and asks, in Hindi, "मेरी रिपोर्ट कब तैयार होगी?" ("When will my report be ready?").
Result. The agent answers in a natural Hindi female voice:
"नमस्ते! आपकी रिपोर्ट कल शाम तक तैयार हो जाएगी। मैं आपको SMS भेज दूँगी।" ("Hello! Your report will be ready by tomorrow evening. I'll send you an SMS.")
Priya starts a follow-up question mid-sentence, and the agent stops talking to listen.
What just happened. Sarvam transcribed Priya's words, the voice brain looked up her report, and Sarvam spoke the reply. Because the voice is female, the agent used "दूँगी" (the feminine form), in speech and in the SMS it sent.
Where to go next
- Voice (Phone and Browser): the voice channels and phone setup.
- AI Model sub-node: the chat, document and vision model settings on the same panel.
- Web Chat: turn on browser voice.