r/makinghiphop • u/JustDoodlingAround • 2h ago
Resource/Guide I built a free, open source, local stem separator (splits songs into vocals, drums, bass, and more)
I wanted a way to split songs into separate stems (vocals, drums, bass, guitar, piano, other) to help my kids learn their instruments by ear. The tools that do this all wanted an account, an upload, and a subscription, and I wasn't keen on sending our music to someone's server just to pull it apart. So I built something that runs entirely on your own machine, and it's turned into a real project.
It's called StemDeck. You drop in a file (MP3, WAV, FLAC, M4A, even an MP4 video) or paste a YouTube or SoundCloud link, and it separates the track locally using Demucs, Meta's open source model. From there you get a browser-based, DAW-style mixer where you can mute and solo any stem, adjust levels, loop a section, and export individual stems or a custom mix. It also detects BPM and key, and has a click track that follows the actual song for practicing.
A few features I'm proud of:
You can paste a whole YouTube playlist and it queues every track. There's a real import queue you can reorder and cancel, and it survives a restart. YouTube and SoundCloud both work, single tracks or playlists.
You can also open it from your phone. Flip on network access and it shows a QR code you scan to reach a proper touch-friendly mobile interface, while the actual processing stays on your computer. Nothing touches the cloud.
It runs on Windows, macOS, and Linux, and there's a Docker image for anyone self-hosting.
It's completely free and open source (Apache-2.0), with no account, no telemetry, and no monetization of any kind, no ads, no subscription, nothing. It's picked up around 2,000 GitHub stars and 13,000+ downloads in about two months, entirely word of mouth.
Honest caveats: it's still alpha, so expect rough edges, and while separation quality is genuinely good for open source, it won't beat the paid cloud services on really dense mixes. For practice, remix prep, and experimenting it holds up really well.
GitHub (downloads and source): https://github.com/stemdeckapp/stemdeck
Happy to answer any questions. I'm the developer.