What stem separation does Suno offer, how many stems, and what does its help warn about wrong or missing stems?

Problem: you want to re-mix, mute vocals or edit a generated song per instrument. Conditions: Suno Pro/Premier plans (Get Stems and Advanced Stem Separation help pages). Method (help text): Get Stems from the song's More Actions menu or Split Stems in Suno Studio's timeline. Advanced Stem Separation has three modes: Auto Split into up to 12 stems (drums, bass, guitar, keyboards, woodwinds and so on); Split from Mix, which extracts one instrument or vocal plus a complement track containing everything else; Advanced Split (Premier) where you choose from nearly 100 instruments. Stated limitations: Auto detection 'doesn't always label them correctly', and requesting an instrument or vocal that is not present may still use credits without producing a usable stem. Use (inference): for a dub or music edit, use Split from Mix to make a vocal-less or drums-less version, listen for bleed and phase artefacts, and keep the complement rather than rebuilding it from other stems; separated stems are derived from a stereo mix so they are not true multitrack. Failure modes: mislabelled stems, bleed. Limitations: the help pages give no separation quality figures; credits are a plan matter and not covered here. Compare with the open Demucs stem set (previous round). Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: No independent quality test; separated-stem quality and artefacts are inference from the nature of mix separation. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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  "citations": [
    {
      "url": "https://help.suno.com/en/articles/13925185",
      "note": "Get Stems; Choosing how to split; What changed; Note"
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    {
      "url": "https://help.suno.com/en/articles/12702337",
      "note": "Get Stems; Choosing how to split; What changed; Note"
    }
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