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Glossary

Stems

The separate parts of a music track, each saved as its own file, that play back together as the full mix.

Updated

Stems are the separate parts of a piece of music, each exported as its own audio file: for example the drums, the bass and everything else. Played together from the same start time, they add up to the full mix; played alone or at different levels, they let you rearrange the track without a music editor.

Why stems help in video

A finished mix is all or nothing: you can only turn the whole track up or down. With stems you choose which parts play when:

  • Under a voice. Drums and busy parts compete with speech. Leave the drums out, or very low, while someone talks and keep the music stem quietly underneath; bring the drums back when the voice stops. It is an alternative to ducking the whole track.
  • An intro. Start with the music stem alone, add the bass, then let the drums land on the first big cut.
  • A breakdown. Drop the drums and the bass for a quiet moment before a reveal, then bring everything back on the beat where the reveal lands.

Make these changes on the grid of the music: one beat lasts 60 / BPM seconds (at 124 BPM, 0.48 s) and one bar four beats. Cut scenes on beats and change sections on bars.

Stems in a HyperFrames video

Each stem is its own <audio> element. Give them all the same data-start, so they stay in sync, and set each level separately:

<audio id="bed-music" src="music/loop-afro-sunset-122-music.mp3" data-start="0" data-volume="0.25"></audio>
<audio id="bed-bass" src="music/loop-afro-sunset-122-bass.mp3" data-start="0" data-volume="0.2"></audio>
<audio id="bed-drums" src="music/loop-afro-sunset-122-drums.mp3" data-start="0" data-volume="0.25"></audio>

To bring the drums in later, keep their start time and raise their volume with a volume lane at the bar where they should enter. Starting the drum file later instead would put it out of step with the other parts.

In Motion Cheat Code

Each of the 30 music tracks comes as a seamless loop, as 15, 30 and 60-second edits with a real ending, and as 3 stems: drums, bass and music, which is everything else. The stems are MP3 files in a stems folder inside each track's folder in the Audio Vault. The kit's music folder holds only the loops, so copy the stems you need into your project's music folder and name them in the prompt.

Questions

Do stems add up to the full track?

Yes. Started at the same moment and at the same volume, the drums, bass and music stems of a track play back as the full loop.

Can I use just one stem?

Yes. The music stem on its own makes a softer bed under a voice, and the drums alone can drive a fast montage or a caption sequence.

What is the difference between a stem and an edit?

An edit is the full mix cut to a set length with a real ending. A stem is one part of the mix at the length of the loop. Use edits when the music should finish with the video, and stems when you want to change the arrangement.