MIDI vs Audio
MIDI and audio are two different ways of working with musical material in a project. MIDI stores performance instructions, while audio stores recorded or rendered waveforms. They can be used together, but they offer different editing options.
The Core Difference
MIDI
A set of instructions: "play C4 at velocity 100 for half a beat." It contains no sound and needs an instrument or synthesiser to produce audio. Like sheet music, it describes a performance without being the resulting recording.
+ Change instrument any time
+ Edit individual notes easily
+ Transpose instantly
+ Change tempo without quality loss
+ Tiny file size (kilobytes)
- Needs an instrument to make sound
- Can't capture vocals or acoustic instruments
Audio
A recording or render of sound waves: the signal captured by a microphone or produced by a plugin. The waveform contains the performance as audio, so note editing is less direct than it is with MIDI.
+ Captures real performances
+ What you hear is what you get
+ Works with vocals, guitars, any sound
+ No plugin needed to play back
+ Can include effects baked in
- Hard to change individual notes
- Transposing and tempo changes affect quality
- Large file size (megabytes)
What They Look Like in a DAW
MIDI shows discrete note blocks you can move and resize. Audio shows the continuous waveform of the recorded sound.
When to Use Each
Use MIDI for...
Virtual instruments (synths, piano plugins, drum machines), anything you might want to edit note-by-note, parts you're still experimenting with, and when you want to try different sounds on the same part.
Use Audio for...
Vocals, live instruments (guitar, bass, drums), samples and loops, and when you've finalised a MIDI part and want to "freeze" it to save CPU. Also for anything recorded through a microphone.
Common workflow
Compose with MIDI (easy to change), then bounce to audio once you're happy (saves CPU, locks in the sound). Most producers work with both simultaneously throughout a project.
Bouncing MIDI to Audio
When you "bounce" or "render" a MIDI track, the DAW plays the MIDI through the assigned plugin and records the resulting audio. This converts the instructions into an actual recording. The MIDI data still exists - you're just creating an audio version. This is useful when your computer struggles to run many plugins simultaneously, or when you want to apply audio-only processing.
Try it
Sort these jobs into MIDI, audio, or either: changing one bass note, recording a vocal, swapping a synth patch, and freezing a CPU-heavy instrument. Explain one advantage and one limitation for each choice.
Self-check: note editing and patch swapping favour MIDI; vocals require audio; freezing a synth converts its MIDI performance into audio while preserving the original MIDI as an editable source.
Key takeaway
MIDI is editable instructions with no sound of their own. Audio is a recording of actual sound waves. Use MIDI for composition and flexible editing. Use audio for final recordings and real-world sound capture.
Next: putting it all into practice - how to use MIDI files in your productions.
Work with MIDI data
Starts generates pure MIDI data you can edit, transpose, and reassign freely.