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Audio Separation Callbacks ​

System will call this callback when vocal and instrument separation is complete.

When you submit a vocal separation task to the Suno API, you can use the callBackUrl parameter to set a callback URL. The system will automatically push the results to your specified address when the task is completed.

Callback Mechanism Overview ​

Webhook Security

To ensure the authenticity and integrity of callback requests, we strongly recommend implementing webhook signature verification. See our Webhook Verification Guide for detailed implementation steps.

Callback Timing ​

The system will send callback notifications in the following situations:

  • Vocal separation task completed successfully
  • Vocal separation task failed
  • Errors occurred during task processing

Callback Method ​

  • HTTP Method: POST
  • Content Type: application/json
  • Timeout Setting: 15 seconds

Callback Request Format ​

When the task is completed, the system will send a POST request to your callBackUrl based on the separation type you selected. Different separation types correspond to different callback data structures:

separate_vocal Type Callbacks ​

Success Callback ​

json
{
  "code": 200,
  "msg": "vocal Removal generated successfully.",
  "data": {
    "task_id": "3e63b4cc88d52611159371f6af5571e7",
    "vocal_removal_info": {
      "instrumental_url": "https://file.aiquickdraw.com/s/d92a13bf-c6f4-4ade-bb47-f69738435528_Instrumental.mp3",
      "origin_url": "",
      "vocal_url": "https://file.aiquickdraw.com/s/3d7021c9-fa8b-4eda-91d1-3b9297ddb172_Vocals.mp3",
      "origin_data": [
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Vocals",
          "id": "efb902e8-ade5-467d-b7d0-61fa5e057d51"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Instrumental",
          "id": "f239d1a9-0480-4ae5-ac28-feb7a12553cb"
        }
      ]
    }
  }
}

Failure Callback ​

json
{
  "code": 500,
  "msg": "Vocal separation failed",
  "data": {
    "task_id": "3e63b4cc88d52611159371f6af5571e7"
  }
}

split_stem Type Callbacks ​

Success Callback ​

json
{
  "code": 200,
  "msg": "vocal Removal generated successfully.",
  "data": {
    "task_id": "e649edb7abfd759285bd41a47a634b10",
    "vocal_removal_info": {
      "origin_url": "",
      "backing_vocals_url": "https://file.aiquickdraw.com/s/aadc51a3-4c88-4c8e-a4c8-e867c539673d_Backing_Vocals.mp3",
      "bass_url": "https://file.aiquickdraw.com/s/a3c2da5a-b364-4422-adb5-2692b9c26d33_Bass.mp3",
      "brass_url": "https://file.aiquickdraw.com/s/334b2d23-0c65-4a04-92c7-22f828afdd44_Brass.mp3",
      "drums_url": "https://file.aiquickdraw.com/s/ac75c5ea-ac77-4ad2-b7d9-66e140b78e44_Drums.mp3",
      "fx_url": "https://file.aiquickdraw.com/s/a8822c73-6629-4089-8f2a-d19f41f0007d_FX.mp3",
      "guitar_url": "https://file.aiquickdraw.com/s/064dd08e-d5d2-4201-9058-c5c40fb695b4_Guitar.mp3",
      "keyboard_url": "https://file.aiquickdraw.com/s/adc934e0-df7d-45da-8220-1dba160d74e0_Keyboard.mp3",
      "percussion_url": "https://file.aiquickdraw.com/s/0f70884d-047c-41f1-a6d0-7044618b7dc6_Percussion.mp3",
      "strings_url": "https://file.aiquickdraw.com/s/49829425-a5b0-424e-857a-75d4c63a426b_Strings.mp3",
      "synth_url": "https://file.aiquickdraw.com/s/56b2d94a-eb92-4d21-bc43-3460de0c8348_Synth.mp3",
      "vocal_url": "https://file.aiquickdraw.com/s/07420749-29a2-4054-9b62-e6a6f8b90ccb_Vocals.mp3",
      "woodwinds_url": "https://file.aiquickdraw.com/s/d81545b1-6f94-4388-9785-1aaa6ecabb02_Woodwinds.mp3",
      "origin_data": 
      [
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Vocals",
          "id": "aea2a703-6f8f-494d-b75f-1707a204b6b3"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Backing_Vocals",
          "id": "e8fbb979-e5aa-4383-b047-b3f477ade352"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Drums",
          "id": "c03975d4-6e0a-4035-8e63-051a6645d341"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Bass",
          "id": "87d276bc-0934-4867-963d-53260b2c2a3a"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Guitar",
          "id": "2e528c6e-fb86-4102-a7c5-99f2924c8ec9"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Keyboard",
          "id": "085ce0bf-7683-49d2-b640-ab682cd821bb"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Percussion",
          "id": "eac93cca-b286-4e55-ad56-da0809fde10e"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Strings",
          "id": "b9fc0b0c-03ad-4d57-a750-9a781ca4e533"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Synth",
          "id": "0c45fb26-a317-40bb-8ff7-1b9d48a41d4b"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "FX",
          "id": "d6ef4126-b05c-42b5-aa3e-6b10ab545caf"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Brass",
          "id": "f3f5e600-0de4-4278-afb9-56858de13402"
        },
        {
          "duration": 240,
          "audio_url": "https://example/s/3*****s.mp3",
          "stem_type_group_name": "Woodwinds",
          "id": "433ec06c-787f-4a89-ae91-7bd8c9c6c1c1"
        }
    ]
    }
  }
}

Failure Callback ​

json
{
  "code": 500,
  "msg": "Instrument separation failed",
  "data": {
    "task_id": "e649edb7abfd759285bd41a47a634b10"
  }
}

split_stem_advanced Type Callbacks ​

Success Callback ​

json
{
    "code": 200,
    "msg": "vocal Removal generated successfully.",
    "data": {
        "task_id": "7220be2955295dda60de46ec6e4ead4c",
        "vocal_removal_info": {
            "origin_data": [
                {
                    "extract": {
                        "duration": 194.92,
                        "audio_url": "https://tempfile.aiquickdraw.com/r/eb7d0f18-8349-4735-a65e-1812705d5ddf_Lead Vocal.mp3",
                        "stem_type_group_name": "Lead Vocal",
                        "id": "eb7d0f18-8349-4735-a65e-1812705d5ddf"
                    },
                    "remove": {
                        "duration": 194.92,
                        "audio_url": "https://tempfile.aiquickdraw.com/r/706d32df-e988-412e-bce4-42c9302e5478_Lead Vocal.mp3",
                        "stem_type_group_name": "Lead Vocal",
                        "id": "706d32df-e988-412e-bce4-42c9302e5478"
                    }
                },
                {
                    "extract": {
                        "duration": 194.92,
                        "audio_url": "https://tempfile.aiquickdraw.com/r/a7c503f6-1265-4f7e-bf5d-c50fb3b07238_Lead Vocal.mp3",
                        "stem_type_group_name": "Lead Vocal",
                        "id": "a7c503f6-1265-4f7e-bf5d-c50fb3b07238"
                    },
                    "remove": {
                        "duration": 194.92,
                        "audio_url": "https://tempfile.aiquickdraw.com/r/a3a0c954-1980-410f-9b34-8539b8eb23f8_Lead Vocal.mp3",
                        "stem_type_group_name": "Lead Vocal",
                        "id": "a3a0c954-1980-410f-9b34-8539b8eb23f8"
                    }
                }
            ],
            "origin_url": ""
        }
    }
}

Failure Callback ​

json
{
    "code": 500,
    "data": {
        "task_id": "0f4283e1df41e18f7177efbcecd839a1"
    },
    "msg": "vocal Removal generation failed."
}

Status Code Description ​

code (integer, required) ​

Callback status code indicating task processing result:

Status CodeDescription
200Success - Request has been processed successfully
500Internal Error - Please try again later

msg (string, required) ​

Status message providing detailed status description

data.task_id (string, required) ​

Task ID, consistent with the task_id returned when you submitted the task

data.vocal_removal_info (object) ​

Vocal separation result information, returned on success. The returned fields depend on the separation type (type parameter)

separate_vocal Type Callback Fields ​

data.vocal_removal_info.instrumental_url (string) ​

Instrumental part audio URL (separate_vocal type only)

data.vocal_removal_info.origin_url (string) ​

Original audio URL

data.vocal_removal_info.vocal_url (string) ​

Vocal part audio URL

split_stem Type Callback Fields ​

data.vocal_removal_info.origin_url (string) ​

Original audio URL

data.vocal_removal_info.vocal_url (string) ​

Main vocal audio URL

data.vocal_removal_info.backing_vocals_url (string) ​

Backing vocals audio URL (split_stem type only)

data.vocal_removal_info.drums_url (string) ​

Drums part audio URL (split_stem type only)

data.vocal_removal_info.bass_url (string) ​

Bass part audio URL (split_stem type only)

data.vocal_removal_info.guitar_url (string) ​

Guitar part audio URL (split_stem type only)

data.vocal_removal_info.keyboard_url (string) ​

Keyboard part audio URL (split_stem type only)

data.vocal_removal_info.percussion_url (string) ​

Percussion part audio URL (split_stem type only)

data.vocal_removal_info.strings_url (string) ​

Strings part audio URL (split_stem type only)

data.vocal_removal_info.synth_url (string) ​

Synthesizer part audio URL (split_stem type only)

data.vocal_removal_info.fx_url (string) ​

Effects part audio URL (split_stem type only)

data.vocal_removal_info.brass_url (string) ​

Brass part audio URL (split_stem type only)

data.vocal_removal_info.woodwinds_url (string) ​

Woodwinds part audio URL (split_stem type only)

split_stem_advanced Callback Fields ​

data.vocal_removal_info.origin_data (array) ​

An array of separation results for the original audio, containing extraction and removal information for multiple stem groups. Each element represents an independent stem group (e.g., Lead Vocal).

data.vocal_removal_info.origin_data[].extract (object) ​

Information about the extracted target stem (isolates this stem while removing others).

data.vocal_removal_info.origin_data[].extract.duration (number) ​

The duration of the extracted audio, in seconds.

data.vocal_removal_info.origin_data[].extract.audio_url (string) ​

The download URL of the extracted target stem audio file.

data.vocal_removal_info.origin_data[].extract.stem_type_group_name (string) ​

The stem type group name (e.g., Lead Vocal), indicating which type of stem this group extracts.

data.vocal_removal_info.origin_data[].extract.id (string) ​

The unique identifier for the extracted audio.

data.vocal_removal_info.origin_data[].remove (object) ​

Information about the remaining audio after removing the target stem (removes this stem while keeping others).

data.vocal_removal_info.origin_data[].remove.duration (number) ​

The duration of the audio after removal, in seconds.

data.vocal_removal_info.origin_data[].remove.audio_url (string) ​

The download URL of the remaining audio file after the target stem has been removed.

data.vocal_removal_info.origin_data[].remove.stem_type_group_name (string) ​

The stem type group name (e.g., Lead Vocal), consistent with the corresponding extract entry.

data.vocal_removal_info.origin_data[].remove.id (string) ​

The unique identifier for the remaining audio.

Callback Reception Examples ​

Below are example codes for receiving callbacks in popular programming languages:

Node.js ​

javascript
const express = require('express');
const app = express();

app.use(express.json());

app.post('/suno-vocal-separation-callback', (req, res) => {
  const { code, msg, data } = req.body;
  
  console.log('Received vocal separation callback:', {
    taskId: data.task_id,
    status: code,
    message: msg
  });
  
  if (code === 200) {
    // Task completed successfully
    console.log('Vocal separation completed');
    const vocalInfo = data.vocal_removal_info;
    
    if (vocalInfo) {
      console.log('Separation results:');
      console.log(`Original audio: ${vocalInfo.origin_url}`);
      console.log(`Vocal part: ${vocalInfo.vocal_url}`);
      
      if (vocalInfo.instrumental_url) {
        console.log(`Instrumental part: ${vocalInfo.instrumental_url}`);
      }
      
      if (vocalInfo.backing_vocals_url) {
        console.log(`Backing vocals: ${vocalInfo.backing_vocals_url}`);
        console.log(`Drums part: ${vocalInfo.drums_url}`);
        console.log(`Bass part: ${vocalInfo.bass_url}`);
        console.log(`Guitar part: ${vocalInfo.guitar_url}`);
        console.log(`Keyboard part: ${vocalInfo.keyboard_url}`);
        console.log(`Percussion part: ${vocalInfo.percussion_url}`);
        console.log(`Strings part: ${vocalInfo.strings_url}`);
        console.log(`Synthesizer part: ${vocalInfo.synth_url}`);
        console.log(`Effects part: ${vocalInfo.fx_url}`);
        console.log(`Brass part: ${vocalInfo.brass_url}`);
        console.log(`Woodwinds part: ${vocalInfo.woodwinds_url}`);
      }
    }
    
  } else {
    console.log('Vocal separation failed:', msg);
  }
  
  res.status(200).json({ status: 'received' });
});

app.listen(3000, () => {
  console.log('Callback server running on port 3000');
});

Python ​

python
from flask import Flask, request, jsonify
import requests
import os

app = Flask(__name__)

@app.route('/suno-vocal-separation-callback', methods=['POST'])
def handle_callback():
    data = request.json
    
    code = data.get('code')
    msg = data.get('msg')
    callback_data = data.get('data', {})
    task_id = callback_data.get('task_id')
    vocal_info = callback_data.get('vocal_removal_info')
    
    print(f"Received vocal separation callback: {task_id}, status: {code}, message: {msg}")
    
    if code == 200:
        print("Vocal separation completed")
        
        if vocal_info:
            print("Separation results:")
            print(f"Original audio: {vocal_info.get('origin_url')}")
            print(f"Vocal part: {vocal_info.get('vocal_url')}")
            
            if vocal_info.get('instrumental_url'):
                print(f"Instrumental part: {vocal_info.get('instrumental_url')}")
            
            if vocal_info.get('backing_vocals_url'):
                print(f"Backing vocals: {vocal_info.get('backing_vocals_url')}")
                print(f"Drums part: {vocal_info.get('drums_url')}")
                print(f"Bass part: {vocal_info.get('bass_url')}")
                print(f"Guitar part: {vocal_info.get('guitar_url')}")
                print(f"Keyboard part: {vocal_info.get('keyboard_url')}")
                print(f"Percussion part: {vocal_info.get('percussion_url')}")
                print(f"Strings part: {vocal_info.get('strings_url')}")
                print(f"Synthesizer part: {vocal_info.get('synth_url')}")
                print(f"Effects part: {vocal_info.get('fx_url')}")
                print(f"Brass part: {vocal_info.get('brass_url')}")
                print(f"Woodwinds part: {vocal_info.get('woodwinds_url')}")
            
            # Download example
            def download_audio_file(url, filename):
                if url:
                    try:
                        response = requests.get(url)
                        if response.status_code == 200:
                            with open(filename, "wb") as f:
                                f.write(response.content)
                            print(f"Saved: {filename}")
                    except Exception as e:
                        print(f"Download failed {filename}: {e}")
            
            os.makedirs(f"vocal_separation_{task_id}", exist_ok=True)
            download_audio_file(vocal_info.get('vocal_url'), 
                              f"vocal_separation_{task_id}/vocal.mp3")
            
            if vocal_info.get('instrumental_url'):
                download_audio_file(vocal_info.get('instrumental_url'), 
                                  f"vocal_separation_{task_id}/instrumental.mp3")
            
            if vocal_info.get('backing_vocals_url'):
                stem_files = {
                    'backing_vocals': vocal_info.get('backing_vocals_url'),
                    'drums': vocal_info.get('drums_url'),
                    'bass': vocal_info.get('bass_url'),
                    'guitar': vocal_info.get('guitar_url'),
                    'keyboard': vocal_info.get('keyboard_url'),
                    'percussion': vocal_info.get('percussion_url'),
                    'strings': vocal_info.get('strings_url'),
                    'synth': vocal_info.get('synth_url'),
                    'fx': vocal_info.get('fx_url'),
                    'brass': vocal_info.get('brass_url'),
                    'woodwinds': vocal_info.get('woodwinds_url')
                }
                for name, url in stem_files.items():
                    download_audio_file(url, f"vocal_separation_{task_id}/{name}.mp3")
            
    else:
        print(f"Vocal separation failed: {msg}")
    
    return jsonify({'status': 'received'}), 200

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=3000)

PHP ​

php
<?php
header('Content-Type: application/json');

$input = file_get_contents('php://input');
$data = json_decode($input, true);

$code = $data['code'] ?? null;
$msg = $data['msg'] ?? '';
$callbackData = $data['data'] ?? [];
$taskId = $callbackData['task_id'] ?? '';
$vocalInfo = $callbackData['vocal_removal_info'] ?? null;

error_log("Received vocal separation callback: $taskId, status: $code, message: $msg");

if ($code === 200) {
    error_log("Vocal separation completed");
    
    if ($vocalInfo) {
        error_log("Separation results:");
        error_log("Original audio: " . ($vocalInfo['origin_url'] ?? ''));
        error_log("Vocal part: " . ($vocalInfo['vocal_url'] ?? ''));
        
        if (!empty($vocalInfo['instrumental_url'])) {
            error_log("Instrumental part: " . $vocalInfo['instrumental_url']);
        }
        
        if (!empty($vocalInfo['backing_vocals_url'])) {
            error_log("Backing vocals: " . $vocalInfo['backing_vocals_url']);
            error_log("Drums part: " . ($vocalInfo['drums_url'] ?? ''));
            error_log("Bass part: " . ($vocalInfo['bass_url'] ?? ''));
            error_log("Guitar part: " . ($vocalInfo['guitar_url'] ?? ''));
            error_log("Keyboard part: " . ($vocalInfo['keyboard_url'] ?? ''));
            error_log("Percussion part: " . ($vocalInfo['percussion_url'] ?? ''));
            error_log("Strings part: " . ($vocalInfo['strings_url'] ?? ''));
            error_log("Synthesizer part: " . ($vocalInfo['synth_url'] ?? ''));
            error_log("Effects part: " . ($vocalInfo['fx_url'] ?? ''));
            error_log("Brass part: " . ($vocalInfo['brass_url'] ?? ''));
            error_log("Woodwinds part: " . ($vocalInfo['woodwinds_url'] ?? ''));
        }
        
        function downloadAudioFile($url, $filename) {
            if (!empty($url)) {
                try {
                    $audioContent = file_get_contents($url);
                    if ($audioContent !== false) {
                        file_put_contents($filename, $audioContent);
                        error_log("Saved: $filename");
                    }
                } catch (Exception $e) {
                    error_log("Download failed $filename: " . $e->getMessage());
                }
            }
        }
        
        $dir = "vocal_separation_$taskId";
        if (!is_dir($dir)) {
            mkdir($dir, 0777, true);
        }
        
        downloadAudioFile($vocalInfo['vocal_url'] ?? '', "$dir/vocal.mp3");
        
        if (!empty($vocalInfo['instrumental_url'])) {
            downloadAudioFile($vocalInfo['instrumental_url'], "$dir/instrumental.mp3");
        }
        
        if (!empty($vocalInfo['backing_vocals_url'])) {
            $stemFiles = [
                'backing_vocals' => $vocalInfo['backing_vocals_url'] ?? '',
                'drums' => $vocalInfo['drums_url'] ?? '',
                'bass' => $vocalInfo['bass_url'] ?? '',
                'guitar' => $vocalInfo['guitar_url'] ?? '',
                'keyboard' => $vocalInfo['keyboard_url'] ?? '',
                'percussion' => $vocalInfo['percussion_url'] ?? '',
                'strings' => $vocalInfo['strings_url'] ?? '',
                'synth' => $vocalInfo['synth_url'] ?? '',
                'fx' => $vocalInfo['fx_url'] ?? '',
                'brass' => $vocalInfo['brass_url'] ?? '',
                'woodwinds' => $vocalInfo['woodwinds_url'] ?? ''
            ];
            foreach ($stemFiles as $name => $url) {
                downloadAudioFile($url, "$dir/$name.mp3");
            }
        }
    }
    
} else {
    error_log("Vocal separation failed: $msg");
}

http_response_code(200);
echo json_encode(['status' => 'received']);
?>

Best Practices ​

Callback URL Configuration Recommendations

  1. Use HTTPS: Ensure callback URL uses HTTPS protocol for secure data transmission
  2. Verify Origin: Verify the legitimacy of the request source in callback processing
  3. Idempotent Processing: The same task_id may receive multiple callbacks, ensure processing logic is idempotent
  4. Quick Response: Callback processing should return 200 status code quickly to avoid timeout
  5. Asynchronous Processing: Complex business logic should be processed asynchronously to avoid blocking callback responses
  6. Type-based Processing: Handle different audio file structures based on different separation types
  7. Batch Download: split_stem type produces multiple files, recommend batch downloading and organizing by type

Important Reminders

  • Callback URL must be publicly accessible
  • Server must respond within 15 seconds, otherwise will be considered timeout
  • If 3 consecutive retry attempts fail, the system will stop sending callbacks
  • Please ensure the stability of callback processing logic to avoid callback failures due to exceptions
  • Vocal separation generated audio file URLs may have time limits, recommend downloading and saving promptly
  • Note that some audio part URLs may be empty, certain instrument separations might be empty
  • separate_vocal and split_stem types return different fields, please handle corresponding fields based on the type parameter in the request

Troubleshooting ​

If you are not receiving callback notifications, please check the following:

Network Connection Issues
  • Confirm callback URL is accessible from public internet
  • Check firewall settings to ensure inbound requests are not blocked
  • Verify domain name resolution is correct
Server Response Issues
  • Ensure server returns HTTP 200 status code within 15 seconds
  • Check server logs for error messages
  • Verify endpoint path and HTTP method are correct
Content Format Issues
  • Confirm received POST request body is in JSON format
  • Check if Content-Type is application/json
  • Verify JSON parsing is correct
File Processing Issues
  • Confirm all audio file URLs are accessible
  • Check file download permissions and network connection
  • Verify file save path and permissions
  • Note that some instrument separation results may be empty
  • Note the field differences between separate_vocal and split_stem types

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