1.What is MIDI? 2.MIDI Notes & Velocity 3.Quantisation 4.What is a DAW? 5.MIDI vs Audio 6.Using MIDI Files
Lesson 2

MIDI Notes & Velocity

MIDI notes and velocity explained - how MIDI represents pitch, timing, and dynamics with numbers. Master the piano roll in your DAW. Free interactive lesson.

By the end: You can edit a MIDI note's pitch, timing, duration, and velocity in a piano roll to produce an intended musical phrase.

MIDI Notes & Velocity

MIDI represents every musical note as a number from 0 to 127. It also records how hard each note is played using a separate number called velocity. Together, note number and velocity give you precise control over pitch and dynamics - the note number identifies the pitch, while velocity supplies performance data that an instrument may map to loudness or timbre.

Note Numbers (0-127)

Each semitone on the keyboard gets a number. Going up one semitone adds 1, and going up one octave adds 12 because an octave contains 12 semitones.

Note MIDI Number Common Use
C1 (24) 24 Sub bass
C2 (36) 36 Bass notes, kick drum (GM)
C3 (48) 48 Low chords, bass guitar upper range
C4 (Middle C) 60 Reference point - centre of the keyboard
C5 (72) 72 Melodies, lead lines
C6 (84) 84 High melodies, sparkle
C7 (96) 96 Very high - effects, bells

Note: some DAWs label middle C as C3 instead of C4. The MIDI number (60) is always the same regardless of labelling.

Quick Formula

To find any note's MIDI number: start with C in that octave and count semitones up. C4 = 60, so D4 = 62 (two semitones up), E4 = 64, F4 = 65, and so on. Or remember that each octave is 12 apart: C3 = 48, C4 = 60, C5 = 72.

Velocity (0-127)

Velocity is a note-on value from 0 to 127 that commonly represents playing intensity. On an acoustic piano, hammer speed affects volume and timbre; MIDI uses the same control name, but each instrument decides how its velocity response is mapped.

ppp 16 pp 33 p 49 mp 64 mf 80 f 96 ff 112 fff 127

Velocity in Practice

Velocity is not necessarily just volume. Depending on the instrument, it may affect several parts of the sound:

Volume

Many instruments map higher velocity to a louder note, but the exact curve depends on the patch.

Brightness

A patch may map higher velocity to filter cutoff or another timbral change, making the note brighter or more cutting.

Sample Selection

Some sampled instruments switch or blend recordings across velocity layers, so a soft piano sample can differ from a harder one.

Attack Speed

A synth patch may map velocity to attack time or transient level, making harder notes more immediate.

Why Velocity Variation Matters

A repeated part with every note at 100 can sound static, especially when the source is meant to suggest a performed instrument. Start by shaping the accents that serve the rhythm, then add small variations such as 90-110 where they fit. A DAW's "humanise" function can help, but inspect its timing and velocity changes rather than accepting them blindly.

Try it

MIDI note numbers map directly to pitches, and velocity changes the feel even when the pitch stays fixed.

Velocity shapes the groove even before you change pitch.

Then tap these to hear how MIDI numbers correspond to notes on the keyboard:

Every 12 MIDI numbers = one octave higher

Key takeaway

MIDI notes 0-127 map every pitch across the full range. Velocity 0-127 captures dynamics - how hard each note is played. Together they give precise, editable control over both pitch and expression.

Next: how to tighten up timing and add groove to your performances - quantisation.

See MIDI numbers in action

Starts generates MIDI with varied velocities and note ranges you can export and study.