# ACE Step Audio To Audio API

> Remixa una traccia esistente o sostituisce i testi, guidato dai tag originali e nuovi

Parte da un `audio_url` con i relativi `original_tags` e applica nuovi `tags` per modificarne lo stile. `edit_mode` può essere remix, che modifica il suono complessivo, oppure lyrics, che modifica solo ciò che viene cantato. Puoi fornire `original_lyrics` e nuovi `lyrics`, oltre a `original_seed` se noto. I parametri dei passaggi e della guida sono gli stessi del resto della famiglia.

- Model id: `ace-step/audio-to-audio`
- Made by: ACE Studio
- Category: Text to Music
- Output: audio
- Price per second of your input audio: $0.0002 / second of input audio (cheapest run $0.001 (1 API credit))
- Run: `POST https://api.doitong.com/v1/run/ace-step/audio-to-audio`
- Quote: `POST https://api.doitong.com/v1/quote/ace-step/audio-to-audio`
- Docs page: https://doitong.com/it/developers/models/ace-step/audio-to-audio

## Pricing

Price: **$0.0002 / second of input audio**. Price per second of your input audio: the input files are measured before the run (length, resolution, frame rate). The quote measures the same files and is exactly what the run charges.

The full example input below costs $0.002 = 2 API credits (10 s input audio × $0.0002).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.com/v1/quote/ace-step/audio-to-audio` with the same JSON body returns the exact price for that input; the quote is exactly what a run charges. Invalid input is never charged and failed or canceled requests are refunded automatically.

## Input parameters

Send either the canonical name or the native field name (not both). Canonical names are the same across models.

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `audio_url` | `audio` | string (audio URL) | yes |  |  | URL del file audio per l'outpainting. |
| `edit_mode` |  | enum (string) | no | `remix` | `lyrics`, `remix` | Modalità di modifica: cambia solo il testo o esegue il remix dell'audio. |
| `original_tags` |  | string | yes |  |  | Tag associati originariamente al file audio. |
| `original_lyrics` |  | string | no | `` |  | Testo associato originariamente al file audio. |
| `tags` |  | string | yes |  |  | Tag di stile audio forniti come generi separati da virgole, con `prompt` disponibile come metodo alternativo per fornirli. |
| `lyrics` |  | string | no | `` |  | Testo cantato, con le sezioni del brano organizzate usando controlli come [verse], [chorus] e [bridge]. Per audio senza testo cantato, ometti questo input o fornisci solo [inst] o [instrumental]. |
| `number_of_steps` |  | integer | no | `27` | 3 – 60 | Numero di passaggi usati durante la generazione audio. |
| `seed` |  | integer \| null | no |  |  | Seed per una generazione riproducibile, scelto casualmente se non fornisci un valore. |
| `scheduler` |  | enum (string) | no | `euler` | `euler`, `heun` | Scheduler usato durante la generazione. |
| `guidance_type` |  | enum (string) | no | `apg` | `cfg`, `apg`, `cfg_star` | Tipo di CFG usato durante la generazione. |
| `granularity_scale` |  | integer | no | `10` | -100 – 100 | Scala di granularità applicata durante la generazione. Aumentarla può ridurre gli artefatti. |
| `guidance_interval` |  | number | no | `0.5` | 0 – 1 | Porzione della pianificazione della generazione che riceve la guida: scegliere 0.5 la limita ai passaggi da 0.25 * infer_steps a 0.75 * infer_steps, lasciando senza guida l'inizio e la fine. |
| `guidance_interval_decay` |  | number | no | `0` | 0 – 1 | Decadimento della guida nell'intervallo di generazione: 0.0 mantiene disabilitato il decadimento; altrimenti, la scala diminuisce nell'intervallo da guidance_scale a min_guidance_scale. |
| `guidance_scale` |  | number | no | `15` | 0 – 200 | Scala della guida applicata durante la generazione. |
| `minimum_guidance_scale` |  | number | no | `3` | 0 – 200 | Scala minima della guida raggiunta dopo il decadimento durante la generazione. |
| `tag_guidance_scale` |  | number | no | `5` | 0 – 10 | Scala della guida dei tag applicata durante la generazione. |
| `lyric_guidance_scale` |  | number | no | `1.5` | 0 – 10 | Scala della guida del testo applicata durante la generazione. |
| `original_seed` |  | integer \| null | no |  |  | Seed associato originariamente al file audio. |

File parameters (`audio`) take a public `https://` URL, a `data:` URI up to 10 MB, or the `file_url` of an upload from `POST /files`.

## Example input

Required parameters only:

```json
{
  "tags": "lofi, hiphop, drum and bass, trap, chill",
  "audio": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
  "original_tags": "lofi, hiphop, drum and bass, trap, chill"
}
```

A fuller example:

```json
{
  "tags": "lofi, hiphop, drum and bass, trap, chill",
  "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
  "original_tags": "lofi, hiphop, drum and bass, trap, chill"
}
```

## Run it

Set `DOITONG_API_KEY` to a key from https://doitong.com/developers/dashboard#keys. `?wait=20` returns the finished request in the same call when it is ready within 20 seconds; otherwise poll `GET /requests/{id}` (it also accepts `?wait=`), or pass `webhook_url`.

### curl

```bash
# Run the model; wait up to 20 s for the finished result in the same call
curl -X POST "https://api.doitong.com/v1/run/ace-step/audio-to-audio?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "tags": "lofi, hiphop, drum and bass, trap, chill",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
    "original_tags": "lofi, hiphop, drum and bass, trap, chill"
  }'

# Still "queued" or "running"? Poll with the id from the response:
curl "https://api.doitong.com/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.com/v1";
const headers = {
  "Authorization": "Bearer " + process.env.DOITONG_API_KEY,
  "Content-Type": "application/json",
};

// Run the model; wait up to 20 s for the finished result in the same call
let res = await fetch(API + "/run/ace-step/audio-to-audio?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "tags": "lofi, hiphop, drum and bass, trap, chill",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
    "original_tags": "lofi, hiphop, drum and bass, trap, chill"
  }),
});
let request = await res.json();
if (!res.ok) throw new Error(request.error.code + ": " + request.error.message);

// Not finished yet: long-poll until it is
while (request.status === "queued" || request.status === "running") {
  res = await fetch(API + "/requests/" + request.id + "?wait=20", { headers });
  request = await res.json();
}
if (request.status !== "succeeded") throw new Error(JSON.stringify(request.error));
console.log(request.outputs.map((o) => o.url), request.cost.credits + " API credits ($" + request.cost.usd + ")");
```

### Python

```python
import os
import requests

API = "https://api.doitong.com/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "tags": "lofi, hiphop, drum and bass, trap, chill",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
    "original_tags": "lofi, hiphop, drum and bass, trap, chill",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/ace-step/audio-to-audio", params={"wait": 20}, json=payload, headers=headers)
request = r.json()
if not r.ok:
    raise RuntimeError(request["error"]["code"] + ": " + request["error"]["message"])

# Not finished yet: long-poll until it is
while request["status"] in ("queued", "running"):
    request = requests.get(API + "/requests/" + request["id"], params={"wait": 20}, headers=headers).json()
if request["status"] != "succeeded":
    raise RuntimeError(request["error"])
print([o["url"] for o in request["outputs"]], request["cost"]["credits"], "API credits", "$" + request["cost"]["usd"])
```

### MCP

The MCP server at `https://api.doitong.com/v1/mcp` exposes the tools `search_models`, `get_model`, `quote`, `run`, `get_request`, `cancel_request`, `list_requests`, `create_upload` and `get_account`. A `run` call for this model:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "run",
    "arguments": {
      "model_id": "ace-step/audio-to-audio",
      "input": {
        "tags": "lofi, hiphop, drum and bass, trap, chill",
        "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
        "original_tags": "lofi, hiphop, drum and bass, trap, chill"
      },
      "wait_seconds": 20
    }
  }
}
```

## Response

Every call returns a request object. `status` is one of `queued`, `running`, `succeeded`, `failed`, `canceled`. `outputs` lists the generated files with URLs on our storage (kept forever, or 7 days with `?storage=temporary`; `storage` says which); `output` is the model's own result object with the same URLs.

```json
{
  "id": "req_8k2m4q7x1z9c3v5b6n0p2r4t",
  "object": "request",
  "model": "ace-step/audio-to-audio",
  "status": "succeeded",
  "created_at": "2026-10-20T12:00:00Z",
  "started_at": "2026-10-20T12:00:02Z",
  "completed_at": "2026-10-20T12:00:09Z",
  "queue_position": null,
  "cost": {
    "credits": 2,
    "usd": "0.002",
    "charged": 2,
    "refunded": 0
  },
  "input": {
    "tags": "lofi, hiphop, drum and bass, trap, chill",
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
    "original_tags": "lofi, hiphop, drum and bass, trap, chill"
  },
  "output": {
    "audio": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp3",
      "content_type": "audio/mpeg",
      "file_name": "0-output.mp3",
      "file_size": 1843200
    },
    "seed": 42,
    "tags": "lofi, hiphop, drum and bass, trap, chill",
    "lyrics": "[inst]"
  },
  "outputs": [
    {
      "type": "audio",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp3",
      "content_type": "audio/mpeg",
      "file_size": 1843200,
      "duration": 12,
      "stored": true
    }
  ],
  "error": null,
  "metrics": {
    "inference_seconds": 6.8
  },
  "urls": {
    "self": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `audio` | object {url, content_type, file_name, file_size} | File audio prodotto dalla generazione. |
| `seed` | integer | Seed casuale usato durante la generazione. |
| `tags` | string | Tag di genere applicati durante la generazione. |
| `lyrics` | string | Testo applicato durante la generazione. |

## Related models

- [ACE Step](https://doitong.com/developers/models/ace-step.md) (`ace-step`): $0.0002 / second
- [ACE Step Audio Inpaint](https://doitong.com/developers/models/ace-step/audio-inpaint.md) (`ace-step/audio-inpaint`): $0.0002 / second of input audio
- [ACE Step Audio Outpaint](https://doitong.com/developers/models/ace-step/audio-outpaint.md) (`ace-step/audio-outpaint`): $0.0002 / second of output audio
- [ACE Step Prompt To Audio](https://doitong.com/developers/models/ace-step/prompt-to-audio.md) (`ace-step/prompt-to-audio`): $0.0002 / second
- [MiniMax Music 3](https://doitong.com/developers/models/minimax/music-3.md) (`minimax/music-3`): $0.002 / second
- [DiffRhythm: Lyrics to Song](https://doitong.com/developers/models/diffrhythm.md) (`diffrhythm`): $0.001 / second
- [Elevenlabs Music](https://doitong.com/developers/models/elevenlabs/music.md) (`elevenlabs/music`): $0.60 / minute of output audio
- [Elevenlabs Music v2](https://doitong.com/developers/models/elevenlabs/music/v2.md) (`elevenlabs/music/v2`): $0.60 / minute of output audio

## Links

- HTML page: https://doitong.com/developers/models/ace-step/audio-to-audio
- All models and guides for AI agents: https://doitong.com/developers/llms.txt
- OpenAPI 3.1 with this model's typed request body: https://doitong.com/developers/openapi.json?model=ace-step/audio-to-audio
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/ace-step/audio-to-audio