# Cast vs a stock music library

A stock library (Epidemic Sound, Artlist, Uppbeat and the rest) sells you a subscription to a catalogue: you search it, audition tracks, find one that nearly fits, and trim it to length. Cast generates the track for this episode instead — sized to your voice, delivered in stems, ducking itself under the speech, and on Plus and Max carrying a commercial license.

The catalogue is the whole problem. A track that "nearly fits" is one you then have to cut, loop or fade to length, and ride the volume on around every sentence — and the fit never gets better than nearly, because the track was not made for your episode.

Then there is the part nobody enjoys: the rights. Stock libraries license by subscription, which means the clearance on an episode you published last year can depend on a subscription you are still paying for. And free tiers often carry conditions — attribution, platform limits, a license that lapses with the subscription — so "free music" is free until a platform, a client or a rights holder asks where it came from.

Cast generates the music inside the same place you edit the episode, so the track knows about your edits: cut a minute of speech and it re-balances. Each export made on a licensed plan comes with its commercial license as a PDF — a document you can point at.

When a library is still the right answer: you want a specific, recognizable, human-composed piece, or a named artist. Generation does not give you that, and Cast ships a curated library for exactly this reason.

- **Both** — A large amount of music you are allowed to use in a monetized show.
- **Stock library only** — Human-composed catalogue tracks, named artists, a specific song you already have in mind.
- **Cast only** — Music generated for this episode, sized to your voice. Stems, not a flat file. Automatic ducking that survives your edits. A commercial license PDF attached to the export.

## Related

- [Is the music licensed for commercial use?](https://mubert.com/tools/cast/docs/licensing)
- [How do I generate music for my episode?](https://mubert.com/tools/cast/docs/generate-music)
- [Is there a library of ready-made music?](https://mubert.com/tools/cast/docs/curated-library)
- [Can I get the music as separate stems?](https://mubert.com/tools/cast/docs/music-stems)

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Source: https://mubert.com/tools/cast/docs/cast-vs-stock-music · Cast docs
Last updated: 2026-09-12