Question 1

What's the difference between the TTS API and the voice calling plan?

Accepted Answer

Two separate products, priced separately. The Pāṇini TTS API ($0.0313/min) is a pure text-to-speech API, you send text, you get back audio. The voice calling plan ($0.055/min) is the full end-to-end agent stack: speech-to-text, LLM reasoning, Pāṇini TTS, telephony and workflow orchestration, all bundled. Building a phone agent? Use the calling plan. Just need TTS audio in your own system? Use the API.

Question 2

Which Indian regional languages and dialects are supported?

Accepted Answer

Pāṇini covers 250+ languages including deep Indian regional dialects: Bhojpuri, Garhwali, Marwari, Saraiki, Assamese, Odia, Sanskrit and many more. Every dialect is billed at the same rate as Hindi or English. No quality tiers, no additional setup.

Question 3

How does the voice quality hold up on a real phone call?

Accepted Answer

Pāṇini is trained for telephony conditions, not just clean studio audio. Natural pacing, accurate intonation and proper prosody across 250+ languages. You can also clone a custom voice from a short sample. Audio is streamed rather than generated as a single block, so there's no lag waiting for a full sentence to render.

Question 4

What happens when a caller talks over the agent, goes silent, or the line is noisy?

Accepted Answer

Interruptions are handled in real time, the agent stops speaking, listens, and continues from where it needs to. Background noise, poor line quality and silence are handled by the STT layer, which is trained on real telephone audio. Hold music is detected so the agent doesn't speak into it.

Question 5

How fast does the agent respond?

Accepted Answer

End-to-end latency is under 500 ms, measured from when the caller finishes speaking to when the agent starts responding. Audio is streamed as the LLM generates output, which keeps the conversation feeling continuous. Latency is consistent across all 250+ supported languages.

Question 6

Can I use my existing phone numbers?

Accepted Answer

Both work. Sonex Labs provides managed phone numbers ready to use immediately. If you already have numbers with Exotel, Twilio or another provider, you connect them without migration. WhatsApp and SMS are available as add-ons.

Question 7

Can the agent look up live data mid-call?

Accepted Answer

Yes. The agent queries your systems during the conversation, not just at the start. We support MCP, REST API calls, webhooks and native connectors for HubSpot, Salesforce and others.

Question 8

Can it transfer to a human?

Accepted Answer

Live transfer is built in. You configure the escalation trigger, a keyword, a sentiment threshold, a specific intent, and the agent hands off instantly with full conversation context passed to the human.

Question 9

Is there a free tier?

Accepted Answer

Yes, no card required. The free tier includes 10,000 TTS characters and one voice clone. Unlimited agents, the Sonex Flows workflow builder, full API access, CRM integrations, MCP and tool calling, RBAC and webhooks are included at no cost.

Question 10

Is my data secure? What compliance frameworks are supported?

Accepted Answer

All calls, transcripts and customer records are encrypted end-to-end in transit and at rest. Every workspace is tenant-isolated. Sonex Labs is GDPR, CCPA, HIPAA-ready and DPDP compliant, with full audit trails. Enterprise customers can deploy in a private VPC or on-premises for complete data residency control.

Question 11

Is Pāṇini TTS a good ElevenLabs alternative?

Accepted Answer

Pāṇini covers 250+ languages including deep Indian regional dialects, generates audio in under 500ms, and clones a voice from a 10-second sample. The API is $0.0313/min, billed per 1,000 characters, the same rate across every language with no per-language tiers.

Question 12

Is Sonex Labs a good alternative to Bland AI or Vapi?

Accepted Answer

Sonex Labs pairs Pāṇini TTS with the full Sonex Flows calling stack, speech-to-text, LLM reasoning, telephony and workflow orchestration, at $0.055/min end to end. It adds native support for Indian regional dialects (Bhojpuri, Marwari, Garhwali and more) at no extra cost, which most alternatives don't cover.

Changelog