# AI stem splitter: vocals, drums, bass, and other

Break any song into four stereo stems for remixing, practice, or sampling.

## Four-stem source separation with SCNet XL

Audo's AI stem splitter and audio stem splitter breaks mastered recordings into four studio stems (WAV, MP3, M4A, AAC, FLAC, OGG, Opus, WebM, AIFF) up to 10 GB without an account, with the first 45 seconds free 3 times a day and no sign-up. Whether you are building a DJ edit, transcribing a bassline, or studying drum groove pocket, having isolated tracks turns a finished stereo master back into a multitrack session.

Behind the scenes, Audo runs SCNet XL (Sparse Compression Network), a dual-path frequency architecture that splits the spectrogram into low, mid, and high sub-bands with different resolution strides. Kick drums and bass guitar fundamentals sit below 250 Hz where fine frequency resolution matters most, while snare transients and hi-hats sit in the upper bands where fast time resolution keeps hits crisp.

Every stem is exported at full 44.1 kHz stereo without dynamic range compression, so when you sum the four files together in your mixer they reconstruct the balance of the original song.

Tool: Split stems (`split_audio`). The same tool's other pages: https://audo.ai/vocal-remover.md, https://audo.ai/karaoke-maker.md, https://audo.ai/remove-music-from-video.md. Price: 8 credits a minute — $0.08/min ($4.80/hr), with no subscription — of input for whole files, charged only when a job succeeds.

## Free API

```bash
curl -F file=@song.wav -F stems=four_stems https://audo.ai/api/try/split-stems -D response.headers -o response.body
```

Read response.headers and response.body before naming media. Handle 202, 200 JSON and errors with the complete response client at https://audo.ai/docs/api?utm_source=markdown&utm_medium=agent#responses.

Free for the first 45 seconds of each file, 3 times a day per person, with no key or account. Uploads up to 10 GB, 2 at once from one address. The response is the result itself; a job that runs longer than about 30 seconds returns 202 with a link to check on it. With an API key (`-H "Authorization: Bearer $AUDO_API_KEY"`), omitting free runs the whole file with credits if the balance covers it, otherwise the free portion if quota remains. Set free=true to prohibit spending; for paid whole files use free=false with an approved positive max_credits. A free result cut short comes with finishUrl (and the Audo-Finish-Url header when the response is the file itself): give it to the person, who pays there (from $5, no sign-up), and the whole file runs; keep checking the status link, whose finishedBy names the whole-file job and its own status link. Details: https://audo.ai/docs/api.md

## Options

Form fields with the same names as the MCP tool's inputs:

- `stems`: Which stems to separate: vocals (vocals first, then instrumental), instrumental (instrumental backing track first, then vocals), four_stems (vocals, drums, bass, and other), or dialogue (music-removed mix first, then dialogue, music, and sound effects). Default vocals.
- `output_format`: The result's format: same (as the input; a video stays a video), wav, mp3, m4a, or flac. Default same.

## Languages

Any language: it works on the sound, not the words.

## From an assistant (MCP)

Add https://audo.ai/mcp and sign in (setup for each assistant: https://audo.ai/setup.md). The tool is `split_audio`:

> Separates a song or video into true stereo stems: vocals and instrumental (vocals or instrumental first), 4 stems (vocals, drums, bass, and other), or dialogue, background music, and sound effects (with a music-removed mix first). Works on video: when output_format is same, the first stem keeps the original video picture. Set free to true to do the first 45 seconds at no cost, up to 3 times a day; otherwise it costs 8 credits a minute, charged only if the job succeeds. Returns job_id; then call get_job.

Example: "Use Audo to split song.wav into vocals, drums, bass, and other stems."

## More

- Every tool: https://audo.ai/llms.txt
- OpenAPI: https://audo.ai/api/openapi.json
- This page for people: https://audo.ai/stem-splitter?utm_source=markdown&utm_medium=agent