Traktor shipped a track as four pre-separated parts

The tool moment

In August 2015, Native Instruments launched Stems, an open file format that ships a track as four pre-separated musical parts inside a single file, alongside a free Traktor Pro 2.9 update and three new Traktor Kontrol controllers built around it. An earlier archived version of Native Instruments' own Stems page, from before release, stated the format "will launch in summer 2015." A later archived launch page announces that Native Instruments "is proud to launch Stems," with a promotional offer on Stems-ready hardware stated as valid starting 3 August 2015, the clearest dated anchor either page provides.

What the documents show

Native Instruments' own description defines a Stem file as "an open, multi-channel audio file that contains a track split into four musical elements, bass, drums, vocals, and melody for example," created by a producer using a free Stem Creator Tool before release, not derived algorithmically from an already-mixed stereo file afterward. This is a structural difference from every AI-driven separator elsewhere in this batch: Stems relies on the original producer providing the four parts, and Native Instruments' pages document store partners, Beatport, Juno and Traxsource among them, agreeing to sell tracks in the format, rather than any separation-accuracy claim, since no algorithm is involved for a properly authored Stem file.

What stays with the musician

Because Stems depends on the original producer choosing to release a track in that format, a DJ's creative options are capped by what labels actually make available, not by any technical limit of Traktor itself; Native Instruments' own page frames this as an open ecosystem, inviting "software and hardware developers" to access the specification. A producer authoring a Stem file, meanwhile, still makes every mixing decision about how the four parts are split and balanced before release; the format documents that division, but a human sets it.

Judge it by listening

Because a properly authored Stem file contains parts a producer separated during mixdown rather than parts estimated after the fact, the fair listening comparison is against an AI-driven splitter's algorithmic guess at the same four categories on a track never released in Stems format. This is an editorial suggestion: if you can find both a Stems-format release and a post-hoc separation of a similar track, compare bleed and artifact levels directly, since a producer-authored file should carry none of the crosstalk an estimation algorithm introduces.

• Is the track you want to play actually available in Stems format, or only through after-the-fact separation?
• Does a producer-authored Stems file sound cleaner on the four parts than an AI splitter's estimate of the same categories?
• Does the format's bass, drums, vocals and melody split match how you would actually want to remix this track?

Stems answered the separation question by moving the work upstream to the producer rather than downstream to an algorithm, a distinction Native Instruments' own launch pages document clearly even without a technical accuracy claim to make.