Hume Octave 2 (TTS)
Select via `version: 2` in the TTS request body (`1` = Octave 1, English/Spanish, ~200 ms). Docs still label Octave 2 '(preview)' as of 2026-09-29. Auth header X-Hume-Api-Key. Max 5,000 chars per utterance, 1,000-char descriptions. Formats MP3/WAV/PCM. No Octave 3 announced on Hume's blog through Sept 2026. Speech-to-speech sibling: see hume-evi.
- Input
- text, audio
- Output
- audio
- License
- proprietary
- Pricing
- per 1k characters: $0.15 (per 1K characters overage on Free/Starter/Creator plans; $0.12 Pro, $0.10 Scale, $0.05 Business (plans include monthly character quotas)) source
- Verified
- 2026-09-29
How to call it
| Provider | Model id | Endpoint / URL | Docs |
|---|---|---|---|
| Hume API | version: 2 | https://api.hume.ai/v0/tts | docs |
| Web app | — | platform.hume.ai | — |
Notable capabilities (3)
- LLM-based emotionally intelligent TTS: Speech-language model that infers emotion and delivery from text; natural-language 'acting instructions' steer tone. Octave 2 at half the price of Octave 1, ~100 ms model latency (docs) / under 200 ms (launch blog). source
- 11 languages, instant cloning from 15 s: Arabic, English, French, German, Hindi, Italian, Japanese, Korean, Portuguese, Russian, Spanish; instant voice cloning from a ~15 s recording with accent prediction across languages; voice design from a text prompt (English only). source
- Voice conversion and phoneme editing: Launch post describes voice conversion (swap speaker) and direct phoneme-level pronunciation editing as new capabilities for a speech-language model. source
Emotionally expressive TTS from Hume AI (Octave = "Omni-capable text and voice engine").
curl https://api.hume.ai/v0/tts -H "X-Hume-Api-Key: $HUME_API_KEY" -H "Content-Type: application/json" \
-d '{"version":2,"utterances":[{"text":"I cannot believe it worked!","description":"a delighted, breathless scientist"}]}'
Sources: https://dev.hume.ai/reference/text-to-speech-tts/synthesize-json , https://www.hume.ai/pricing , https://www.hume.ai/blog/octave-2-launch