Stem (music)

In musical notation

Notation stems are visual indicators that extend up or down from a notehead. Their direction and length follow conventional rules: stems usually point up when notes lie below the middle of the staff and down when they lie above it. For chords, stems are drawn from the right or left side so that multiple voices remain readable. Stems also work with flags and beams to indicate shorter note values (eighths, sixteenths, etc.) and to connect groups of notes into rhythmic units.

In audio production

In production, "stems" are mixes of a subset of tracks exported as single files. A typical set of stems for a song might include drums, bass, guitars, keyboards and lead vocals. Stems are higher-level than individual tracks: they reduce many recordings into a manageable number of audio files while retaining flexibility for balance changes, effects processing, or remixing.

Characteristics and uses

• Notation: stems clarify rhythmic grouping, indicate multiple voices on the same staff, and affect beaming and alignment of flags.
• Production: stems simplify collaboration between producers, enable stem mastering, support live DJing or remix tasks, and can aid archiving or re-release projects.
• Stems are commonly delivered as stereo files but can also be mono or multichannel depending on the application.

History and distinctions

The notation stem evolved as Western notation standardized ways to show duration and polyphony; beaming and stem direction conventions developed to improve readability. The production use of stems emerged from the need to share partial mixes during multitrack recording and became more common with digital audio workstations, which make grouping and exporting stems straightforward. Important distinctions to note: a "track" is a single recorded channel, a "stem" is a grouped mix of several tracks, and a "master" is the final stereo file used for release.

For practical guides and technical standards about stems in either context, see this resource: further information on stems.