# ElevenLabs Sound Effects v2 (audio)

> Sound effects from a text description: transitions, interface sounds, foley, ambience and seamless loops for ads. The prompt describes the sound. The model never speaks it.

Status: roasOS API v1.1. Catalog `model-catalog@2026-10-06.v5`, pricing `customer-pricing@2026-11-05.v15`. The endpoint `POST /v1/audio/elevenlabs-sfx-v2` is live. `POST /v1/generations` stays for one minor version as a deprecated alias (see "Today").

## Endpoint
POST https://api.roasos.com/v1/audio/elevenlabs-sfx-v2
Auth: Authorization: Bearer roasos_sk_… (scope api:write). Idempotency-Key required. quote_only / quote_id / webhook_url as in https://docs.roasos.com/llms.txt.

## Good at
Short sounds that sit on a cut or under a scene: a whoosh on a transition, a ding when a price appears, a cash register, footsteps, rain on a window, room tone. Set `duration_seconds` from 0.5 to 22 to land a sound on a cut, or omit it and the model picks a natural length. `prompt_influence` sets how closely the sound follows the words: higher gives less variation. `loop: true` makes a bed that repeats with no audible seam. It has no voice and no speech controls; use a voice model for spoken lines and a music model for music.

## Pricing
Unit: second. Pricing key: `elevenlabs-sfx-v2`.

| request | credits |
|---|---|
| `1s` | 1 |
| `5s` | 1 |
| `22s` | 1 |
| `auto` | 1 |

Credits come from the roasOS pricing table (`MODEL_COSTS`) through the catalog. No other field changes the price.

## Modes
- `text-to-sound-effect`
Provider endpoints: `fal-ai/elevenlabs/sound-effects/v2`.

## Request fields
| field | type | required | default | rule |
|---|---|---|---|---|
| `duration_seconds` | number | no | — | 0.5–22 |
| `loop` | boolean | no | `false` | — |
| `prompt` | string | yes | — | ≥ 1 character; ≤ 1,000 characters |
| `prompt_influence` | number | no | `0.3` | 0–1 |
| `quote_id` | string | no | — | UUID |
| `quote_only` | boolean | no | `false` | — |
| `wait_timeout_seconds` | integer | no | `0` | 0–60 |
| `webhook_url` | string | no | — | https URL; ≤ 4,096 characters |

The schema is strict: a field that is not in this table returns `400 unsupported_option`. Field names are the roasOS role names, one name per role across every family.

## Media
The endpoint accepts no media. Every media role below is refused.
- Refused: `avatar_id`, `elements`, `product_id`, `product_images`, `references`, `reference_images`, `image_url`, `end_image_url`, `scene_id`, `scene_image`, `video_urls`, `video_url`, `audio_urls`, `audio_url`, `voice_id`. A refused role returns `400 unsupported_option`.
- Every URL must be an immutable object on `https://cdn.roasos.com/…` that your workspace owns; any other URL is `400 reference_media_not_workspace_owned`. Upload with `POST /v1/uploads` (direct POST of the bytes to `put_url`, or a `source_url` import), then use the returned CDN URL.

## Prompt
`prompt` limit 1,000 characters. roasOS adds no wrapper.
- Describe the sound, not the scene: the source, the action and the texture. "A heavy wooden door creaks open slowly, then thuds shut."
- Use sound words: whoosh, riser, impact, braam, glitch, swell, drone, foley, ambience, one-shot.
- Say where the sound is: close to the microphone, in a large hall, muffled through a wall.
- Ask for one sound per request. Make each layer of a layered sound its own clip.
- For a loop, describe a steady sound with no clear start or end.
- Raise `prompt_influence` (for example to 0.6) to follow the words closely; lower it (for example to 0.15) for more varied takes.

## Not exposed
- `output_format`: pinned to `mp3_44100_128`.
- `voice`: not accepted by this public endpoint.
- `voice_id`: not accepted by this public endpoint.
- `references`: not accepted by this public endpoint.
- `avatar_id`: not accepted by this public endpoint.
- `product_id`: not accepted by this public endpoint.
- `audio_urls`: not accepted by this public endpoint.
- `image_url`: not accepted by this public endpoint.

## Result
Result kind `audio`. Always present: `url`. Present when the run produces it: `timestamps`.
```json
{ "data": { "id": "gen_…", "kind": "audio", "model": "elevenlabs-sfx-v2", "status": "completed", "result": {"timestamps":[{}],"url":"https://cdn.roasos.com/workspaces/ws_01/result"} } }
```
Files live on `https://cdn.roasos.com` and are immutable; a result URL can be a media input to the next call. Poll `GET /v1/jobs/{id}/status` → `{ id, status, updated_at }`, then `GET /v1/jobs/{id}/result` (`409 run_not_completed` until the job is `completed`, `failed` or `canceled`). Statuses: `queued → processing → completed | failed | canceled`.

## Example
```bash
# 1. quote — nothing is spent
curl -X POST https://api.roasos.com/v1/audio/elevenlabs-sfx-v2 \
  -H "Authorization: Bearer roasos_sk_live_…" \
  -H "Idempotency-Key: 0f1c9e2a-elevenlabs-sfx-v2-0001" \
  -H "Content-Type: application/json" \
  -d '{"quote_only":true,"prompt":"A woman holds the bottle at eye level in a bright kitchen, morning light, static camera."}'
# → 200 { "data": { "kind": "quote", "quote_id": "q_7Hk…", "credits": 1, "expires_at": "…", "confirmation": { "model": "elevenlabs-sfx-v2", "example": "1s" } } }

# 2. run — the same body and the same Idempotency-Key, quote_id instead of quote_only
curl -X POST https://api.roasos.com/v1/audio/elevenlabs-sfx-v2 \
  -H "Authorization: Bearer roasos_sk_live_…" \
  -H "Idempotency-Key: 0f1c9e2a-elevenlabs-sfx-v2-0001" \
  -H "Content-Type: application/json" \
  -d '{"quote_id":"q_7Hk…","prompt":"A woman holds the bottle at eye level in a bright kitchen, morning light, static camera."}'
# → 201 { "data": { "id": "gen_…", "kind": "audio", "model": "elevenlabs-sfx-v2", "status": "queued", "credits_reserved": 1, "links": { "status": "/v1/jobs/gen_…/status", "result": "/v1/jobs/gen_…/result" } } }

# 3. poll
curl https://api.roasos.com/v1/jobs/gen_…/status -H "Authorization: Bearer roasos_sk_live_…"
curl https://api.roasos.com/v1/jobs/gen_…/result -H "Authorization: Bearer roasos_sk_live_…"
```

## Today
`POST /v1/audio/elevenlabs-sfx-v2` is the endpoint. The price is per second of audio: the `duration_seconds` you send, or 22 seconds when you omit it. Nothing is refunded after the run, so send a length when you know it. `POST /v1/generations` also works with `{ "type": "audio", "model": "elevenlabs-sfx-v2", "prompt": "<description>", "options": { "duration_seconds": 3, "prompt_influence": 0.3, "loop": false } }`. The result is one MP3 file.

## See also
https://docs.roasos.com/models/audio/elevenlabs-sfx-v2 · https://api.roasos.com/v1/catalog/audio/elevenlabs-sfx-v2 · fal-ai/elevenlabs/sound-effects/v2