ReportTowards generalist audio models

We’re building one model for all of audio.

It starts with speech. Try kalpa-tts-1 in English and Hindi.

11 voices

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Wrenkalpa-tts-1 · en
kalpa-tts-1English and Hindi~300 ms to first audio, streaming1,000 free minutesGet API key
AudioRealismBench

State-of-the-art audio realism.

Expert listeners hear two clips, blind and in random order, and pick the one that sounds more human. Here is Kalpa TTS Beta V0.1 next to the best models from Cartesia, ElevenLabs and OpenAI, and Eleven v4.

Elo from AudioRealismBench by Design Arena, updated 11 Oct 2026.

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LiveAvailable today

kalpa-tts-1, in the API.

Text-to-speech in eleven voices: English and Hindi, including English words inside Hindi sentences.

~300 msto first audio, streaming
English, HindiDevanagari and code-switching
WebSocketstreamed base64 pcm_s16le
24 kHzmono, 16-bit WAV
1,000 minfree for 3 months
Then a contracthello@kalpalabs.ai
POST/v1/tts/{voice_id}
curl https://api.kalpalabs.ai/v1/tts/5e0c5704-590f-483b-b291-00a2415cb67e \  -H "Authorization: Bearer $KALPA_API_KEY" \  -H "Content-Type: application/json" \  -d '{"text": "नमस्ते! आज आपके लिए क्या पढ़ूँ? कोई story, कोई news, या आपका अपना message?"}'
Response · audio.data_b64200 · 24 kHz
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नमस्ते! आज आपके लिए क्या पढ़ूँ? कोई story, कोई news, या आपका अपना message?
With contextPOST /v1/converse · kalpa-tts-beta-v0.1
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PreviewWhere it’s going

One model you prompt with audio and text.

Text models went from continuing text to following instructions. Most audio models still do one task each. Our base model, trained from random weights on millions of hours of real audio, already takes the first steps.

Continue a sceneThe Godfather · 2.0 s given
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Clone a voice with its deliveryThe Bible, as Love Island
0:15
Broadcast this like 1938 news radioStyle prompt
0:18
Speak like sports commentarySame sentence, another prompt
0:11
Report · 30 Jul 2026

Towards generalist audio models

Prashant Shishodia, Gautam Jha & the Kalpa Labs Team

The architecture, the data, a blind preference eval against four systems, and what the base model can already do.

Read the report
8B backbone, 300M decoder

Interleaved text and audio; 32 codebooks, 31 of them from the RVQ decoder.

From random weights

No text LLM underneath.

Millions of hours, in the wild

Weakly labelled real transcripts; ASR-like ones filtered out.

No denoising

The room is part of who is speaking.

The Turing Clock

A proposed eval: how long can a person talk with a model before deducing, reliably better than 50%, that it is an AI?

Build the first generalist audio model with us.