MIDI, formats and standards · updated 2026-08-16

MIDI

A control protocol, not audio. It sends note, velocity, timing and controller data between instruments and software.

Key takeaways

A control protocol, not audio.
It sends note, velocity, timing and controller data between instruments and software.
That separation is why a MIDI part can be re-voiced, re-timed and transposed indefinitely after the fact, and why a 1983 keyboard can still drive a 2026 plugin.
Record a keyboard part as MIDI, then swap the instrument three times before committing to the sound.
Watch out: expecting MIDI to carry audio.

Quick checklist

Can you define midi in one sentence without looking?
Can you point at midi in a real session, mix or contract?
Have you tried the practical move above at least once?
Would you catch the common mistake before it costs you a take?
Have you opened one of the primary sources below rather than a forum thread?

MIDI IN DEPTH

MIDI carries performance data — note on, note off, velocity, pitch bend, controller values — not audio. That separation is why a MIDI part can be re-voiced, re-timed and transposed indefinitely after the fact, and why a 1983 keyboard can still drive a 2026 plugin.

How it works in practice

Record a keyboard part as MIDI, then swap the instrument three times before committing to the sound.

The mistake people make

Expecting MIDI to carry audio. A MIDI file sent to a collaborator will sound like whatever instruments their system loads, not like your session.

WHERE MIDI SITS

MIDI belongs to midi, formats and standards in the Sampled music glossary. The plumbing — the specs your gear, files and delivery pipeline agree on.

TERMS THAT DEPEND ON MIDI

CV/Gate
Control voltage sets pitch or parameter value; gate says note-on/note-off. The pre-MIDI way modular gear still talks.
Velocity sensitivity
How hard a key is struck, sent as a MIDI value and usually mapped to level and filter brightness so playing dynamics survive.
MPE
MIDI Polyphonic Expression — each note gets its own channel so pitch bend, pressure and slide are per-note.
DAW control surface
Physical faders, knobs and transport buttons that drive your DAW over MIDI or Mackie/HUI protocol. It changes how fast you work, not how anything sounds.
Sustain pedal
A footswitch sending MIDI CC 64. Polarity varies by manufacturer, which is why a pedal sometimes behaves backwards until you flip the setting on the keyboard.

TEST YOURSELF

0/3 answered · 0 correct

3 quick questions on midi. Answers are marked instantly — nothing is sent anywhere.

1. Which statement best describes midi?
2. What is the mistake people most often make with midi?
3. In practice, which of these applies to midi?

Ready for the full thing? Take the 25-question terminology test and get a certificate with your name and score.

SOURCES AND CITATIONS

Free, primary references for midi — standards bodies, manufacturers, government offices and university course material. Each one lists the line of this entry it backs up.

MIDI Association — specifications (opens in a new tab)
Specification owner · The MIDI Association
“A control protocol, not audio.”— the claim this source supports
Why it counts: The body that publishes the MIDI specification, so this is the definition hardware and software are built against.
MIDI Association — MIDI 2.0 (opens in a new tab)
Specification owner · The MIDI Association
“It sends note, velocity, timing and controller data between instruments and software.”— the claim this source supports
Why it counts: The body that publishes the MIDI specification, so this is the definition hardware and software are built against.

RELATED TERMS IN MIDI, FORMATS AND STANDARDS

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