--- title: "Seed Audio 1.0" description: "Text-to-audio from ByteDance: speech with 20 preset voices, or a read that matches up to three reference clips or one reference image. It is best at scene audio, multi-voice reads, and expressive delivery." url: https://docs.roasos.com/models/audio/seed-audio-1.0 --- # Seed Audio 1.0 Family `audio` · model `seed-audio-1.0` · catalog `model-catalog@2026-10-06.v5` · pricing `customer-pricing@2026-11-05.v15` . ## Endpoint ```http POST https://api.roasos.com/v1/audio/seed-audio-1.0 ``` Send your API key as a bearer token. The key needs the scope `api:write`. Every paid request also needs an `Idempotency-Key` header. The envelope fields `quote_only`, `quote_id`, `webhook_url` and `wait_timeout_seconds` behave the same on each model endpoint. Refer to [Jobs](/concepts/jobs) and [Quotes and credits](/concepts/quotes-and-credits). ## Good at The only audio model in the roster that takes references. Give it up to three reference audio clips, name them `@Audio1`, `@Audio2`, `@Audio3` in the prompt, and it matches that timbre and delivery. Give it one reference image instead, and it reads the scene. fal lists it as text-to-audio, so the prompt can direct a whole piece: "Generate a short suspense radio drama in a late-night convenience store." It is the only audio endpoint that exposes `output_format` and `sample_rate`, so use it when you need WAV or PCM. It does not clone a voice into a saved `voice_id`, and it does not accept `avatar_id`. ## Pricing The unit is one **characters**. Pricing key: `seed-audio-1.0`. | Request | Credits | | ----------------- | ------- | | `1000_characters` | 3 | | `2000_characters` | 6 | | `5000_characters` | 15 | The credits come from the roasOS pricing table. No other field changes the price. To get the exact price of your request, send it with `quote_only: true` first. ## Modes * `text-to-speech` Provider endpoints: `bytedance/seed-audio-1.0`. ## Request fields | Field | Type | Required | Default | Rule | | ---------------------- | --------- | -------- | ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `audio_urls` | string\[] | no | — | ≤ 3 items | | `image_url` | string | no | — | https URL; ≤ 4,096 characters | | `output_format` | enum | no | `mp3` | `wav`, `mp3`, `pcm`, `ogg_opus` | | `pitch` | integer | no | `0` | -12–12 | | `quote_id` | string | no | — | UUID | | `quote_only` | boolean | no | `false` | — | | `sample_rate` | enum | no | `24000` | `8000`, `16000`, `24000`, `32000`, `44100`, `48000` | | `speed` | number | no | `1` | 0.5–2 | | `text` | string | yes | — | ≥ 1 character; ≤ 10,000 characters | | `voice` | enum | no | — | `vivi_mixed_en_zh_ja_es_id`, `mindy_en_es_id_pt_zh`, `kian_en_zh`, `cedric_en_zh`, `sophie_en_zh`, `jean_en_zh`, `magnus_en_zh`, `mabel_en_zh`, `nadia_en_zh`, `opal_en_zh`, `pearl_en_zh`, `quentin_en_zh`, `corinne_mixed_en_zh`, `esther_mixed_en_zh`, `lyla_mixed_en_zh`, `tracy_es_zh`, `sandy_es_mixed_en_zh`, `felix_zh`, `celeste_zh`, `monkey_king_zh` | | `volume` | number | no | `1` | 0.5–2 | | `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 gets `400 unsupported_option`. The field names are the roasOS role names. One role has one name in every family. ## Media This endpoint accepts these media roles: * `image_url` — first frame (or the single source image) * `audio_urls` — reference or driving audio | Role | Items | Maximum size | Content types | Duration | | ------------ | ----- | ------------ | ------------------------------------------------------------------- | -------- | | `audio_urls` | ≤ 3 | 15 MB | `audio/mp3`, `audio/mpeg`, `audio/wav`, `audio/wave`, `audio/x-wav` | — | | `image_url` | ≤ 1 | 10 MB | `image/jpeg`, `image/png`, `image/webp` | — | Every other role is refused: `avatar_id`, `elements`, `product_id`, `product_images`, `references`, `reference_images`, `end_image_url`, `scene_id`, `scene_image`, `video_urls`, `video_url`, `audio_url`, `voice_id`. A refused role gets `400 unsupported_option`. Each media URL must be an immutable object on `https://cdn.roasos.com` that your workspace owns. Any other URL gets `400 reference_media_not_workspace_owned` . Refer to [Reference media and uploads](/concepts/reference-media) to learn how to put a file there. ## Prompt `text` limit 10,000 characters. roasOS adds no wrapper and no tags. * Tag syntax: `@Audio1`, `@Audio2`, `@Audio3`, each once, in the order of `audio_urls`: "Read this in the voice of @Audio1: …". * With no reference, write the spoken words and pick a `voice` whose suffix includes the language of the text. * For scene audio, describe the place, the mood, and the speakers in one sentence before the lines. * For a multi-voice read, label the speakers in the text and give one reference clip per speaker. * Keep `speed` near 1; the reservation assumes 12.5 characters per second. * Choose `output_format: "wav"` and `sample_rate: 48000` for a master you will edit further. ## Not exposed These catalog entries describe omitted inputs, pinned values and source constraints. They do not imply that the provider accepts every listed field. * `multilingual` — pinned to `false`. * `audio_urls` — these values are not available: `PCM containers`, `Ogg Opus containers`. * `references` — not accepted by this public endpoint. * `avatar_id` — not accepted by this public endpoint. * `product_id` — not accepted by this public endpoint. * `video_urls` — not accepted by this public endpoint. * `voice_id` — pinned to `the model has no provider voice-clone registry`. * `language` — not accepted by this public endpoint. * `emotion` — not accepted by this public endpoint. * `temperature` — not accepted by this public endpoint. ## Result The result kind is `audio`. Always present: `url`. Present when the run makes it: `timestamps`. ```json { "data": { "id": "gen_…", "kind": "audio", "model": "seed-audio-1.0", "status": "completed", "result": { "timestamps": [ {} ], "url": "https://cdn.roasos.com/workspaces/ws_01/result" } } } ``` The files are immutable objects on `https://cdn.roasos.com`. A result URL is a valid media input for your next request. ## Example The three steps are always the same: quote, run, poll. cURL JavaScript Python ```bash # 1. Quote. Nothing is spent. curl -X POST https://api.roasos.com/v1/audio/seed-audio-1.0 \ -H "Authorization: Bearer roasos_sk_live_..." \ -H "Idempotency-Key: 0f1c9e2a-seed-audio-1.0-0001" \ -H "Content-Type: application/json" \ -d '{"quote_only":true,"text":"Two drops, morning and night. That is the whole routine."}' # 200 { "data": { "kind": "quote", "quote_id": "q_7Hk...", "credits": 3, "expires_at": "...", # "confirmation": { "model": "seed-audio-1.0", "example": "1000_characters" } } } # 2. Run. Same body, same Idempotency-Key, quote_id in place of quote_only. curl -X POST https://api.roasos.com/v1/audio/seed-audio-1.0 \ -H "Authorization: Bearer roasos_sk_live_..." \ -H "Idempotency-Key: 0f1c9e2a-seed-audio-1.0-0001" \ -H "Content-Type: application/json" \ -d '{"quote_id":"q_7Hk...","text":"Two drops, morning and night. That is the whole routine."}' # 201 { "data": { "id": "gen_...", "status": "queued", "credits_reserved": 3 } } # 3. Poll, then read the result. 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_..." ``` ```javascript const key = process.env.ROASOS_API_KEY; const url = "https://api.roasos.com/v1/audio/seed-audio-1.0"; const idempotencyKey = "0f1c9e2a-seed-audio-1.0-0001"; const input = { "text": "Two drops, morning and night. That is the whole routine." }; const post = (payload) => fetch(url, { method: "POST", headers: { Authorization: `Bearer ${key}`, "Idempotency-Key": idempotencyKey, "Content-Type": "application/json", }, body: JSON.stringify(payload), }).then((response) => response.json()); // 1. Quote. Nothing is spent. const quote = await post({ quote_only: true, ...input }); console.log(quote.data.credits); // 2. Run. const job = await post({ quote_id: quote.data.quote_id, ...input }); // 3. Poll, then read the result. let status = "queued"; while (status !== "completed" && status !== "failed" && status !== "canceled") { await new Promise((done) => setTimeout(done, 3000)); const poll = await fetch(`${url.split("/v1")[0]}/v1/jobs/${job.data.id}/status`, { headers: { Authorization: `Bearer ${key}` }, }).then((response) => response.json()); status = poll.data.status; } const result = await fetch(`${url.split("/v1")[0]}/v1/jobs/${job.data.id}/result`, { headers: { Authorization: `Bearer ${key}` }, }).then((response) => response.json()); console.log(result.data.result); ``` ```python import os, time, requests key = os.environ["ROASOS_API_KEY"] url = "https://api.roasos.com/v1/audio/seed-audio-1.0" headers = { "Authorization": f"Bearer {key}", "Idempotency-Key": "0f1c9e2a-seed-audio-1.0-0001", } payload = { "text": "Two drops, morning and night. That is the whole routine." } # 1. Quote. Nothing is spent. quote = requests.post(url, headers=headers, json={"quote_only": True, **payload}).json() print(quote["data"]["credits"]) # 2. Run. job = requests.post(url, headers=headers, json={"quote_id": quote["data"]["quote_id"], **payload}).json() job_id = job["data"]["id"] # 3. Poll, then read the result. jobs = "https://api.roasos.com/v1/jobs" status = "queued" while status not in ("completed", "failed", "canceled"): time.sleep(3) status = requests.get(f"{jobs}/{job_id}/status", headers=headers).json()["data"]["status"] result = requests.get(f"{jobs}/{job_id}/result", headers=headers).json() print(result["data"]["result"]) ``` ## The deprecated path `POST /v1/generations` still reaches this model for one minor version. It is deprecated. This is how it maps: `POST /v1/audio/seed-audio-1.0` is the endpoint. `POST /v1/generations` still works with `{ "type": "audio", "model": "seed-audio-1.0", "prompt": "", "options": { "voice": "kian_en_zh", "audio_urls": ["…"], "output_format": "wav", "sample_rate": "44100", "speed": 1, "volume": 1, "pitch": 0 } }`; there the script goes in `prompt`. Every reference must be a workspace-owned `cdn.roasos.com` object on both surfaces. `options.stability` must be 0.5 and `options.similarity_boost` must be 0.75 (no-op). ## See also * [`llms.txt` for this model](https://docs.roasos.com/models/audio/seed-audio-1.0/llms.txt) — the same facts as one plain-text file for an agent. * `GET https://api.roasos.com/v1/catalog/seed-audio-1.0` — the machine-readable form: enums, defaults, limits and prices. Refer to the [API reference](/api-reference/overview). * [Jobs](/concepts/jobs) — how to poll a job and read its result. * Provider endpoints: `bytedance/seed-audio-1.0`.