TTS Router ids: sonic-3.6 to sonic-preview, one price book

The TTS Router accepts five model ids: sonic-3.6, sonic-3.5, sonic-3, sonic-latest and sonic-preview. Every one bills from the same character book as TTS 1.0, $0.0475 per 1,000 characters at list times 1.25, with a 20,000-character maximum. Pinning a model changes the voice engine, not the price.

Unlike Music, the TTS Router has no automatic mode: model is required on POST /v1/tts-router/generate. List the catalog with GET /v1/tts-router/models.

The ids

When to pin

Pin a numbered id for anything you will re-render later and need to sound the same, such as a series with a recurring narrator. Use sonic-latest when you want improvements to arrive on their own, and accept that a re-render can differ from the first. Keep sonic-preview out of production jobs.

curl -X POST https://api.sume.com/v1/tts-router/generate \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: tts-router-001" \
  -d '{
    "model": "sonic-3.5",
    "transcript": "Welcome back. Today: three ways to cut a long edit.",
    "voice": { "id": "'"$VOICE_ID"'" }
  }'

Cost check

That 52-character line bills $0.01, because each job rounds up to a whole cent. A thousand such lines sent as separate jobs are $10.00. The same 52,000 characters sent in 20,000-character requests would be $2.47, so for bulk work, batch lines into larger scripts and cut the audio afterwards.