What is a MIDI Editor?

ByMunyaradzi Mafaro

MIDI editors are computer programs that let you create, view, and change MIDI data. MIDI stands for Musical Instrument Digital Interface. It is a standard way for electronic musical instruments, computers, and other devices to connect and communicate.

How MIDI Works

MIDI does not contain actual audio or sound. Instead, it is a set of messages or commands that tells a device how to create sound. MIDI messages include information like:

  • Which note to play
  • How long does it take to play the note
  • How loud to play the note
  • What instrument sound to use

When you press a key on a MIDI keyboard, it sends a MIDI message to a connected device, like a computer or synthesizer. The device then plays a sound based on the MIDI information it receives. MIDI data can be recorded, edited, and played back using MIDI hardware and software.

What MIDI Editors Do

MIDI editing software lets you work directly with the MIDI data on your computer. It displays MIDI notes and events as graphics, usually on a piano roll or score view. In a piano roll view, notes are shown as horizontal bars on a grid. The vertical axis represents the pitch, while the horizontal axis represents time.

With a MIDI editor, you can:

  • Create MIDI tracks by drawing in notes with your mouse or computer keyboard
  • Record MIDI tracks by playing them on a MIDI keyboard or pad controller
  • Move, copy, lengthen, shorten, and delete MIDI notes
  • Change the pitch, timing, and velocity (loudness) of MIDI notes
  • Quantize or “snap” notes to a rhythmic grid to fix timing
  • Edit controller data like volume changes, panning, pitch bend, modulation, etc.
  • Choose different virtual instrument sounds from a library to play the MIDI data

Benefits of Using a MIDI Editor

MIDI editing has many advantages compared to audio editing or recording live instruments:

  • You can easily change the notes, timing, tempo, key, and instrumentation after recording
  • You can create complex arrangements and orchestrations beyond your playing ability
  • You can have a computer play backing tracks while you perform live
  • You can mock up musical ideas quickly without using a microphone or live performers
  • The MIDI files are tiny compared to audio files

Many digital audio workstations (DAWs) like Ableton Live, FL Studio, Logic Pro, and Pro Tools have built-in MIDI editing features. There are also standalone MIDI editor programs.

Common MIDI Editor Features

Although MIDI editors vary, most of them have some standard tools and functions:

  • Grid: Shows the timing of notes either in bars/beats or minutes/seconds. The grid spacing or resolution can usually be adjusted.
  • Note Drawing: This lets you draw in notes freehand with a mouse, trackpad, or tablet. You can set the drawn notes’ length, position, and shape.
  • Note Selection: Used for selecting groups of notes to move, copy, edit, or delete together. You can usually choose notes by dragging a box around them.
  • Quantize: Adjust the start time of notes to align them to a rhythmic grid. This tightens up the timing but can make the track sound stiff if overused. Some MIDI editors also have “humanize” functions that add minor random variations to make the timing less perfect.
  • Transpose: Shifts the pitch of selected notes up or down by a chosen interval. This is useful for changing the key of a MIDI sequence.
  • Velocity Editing: MIDI notes have a velocity parameter that controls how loud they sound. MIDI editors represent velocity with different colors or note thicknesses. You can redraw the velocity of individual notes or scale the overall velocity.
  • Automation: MIDI continuous controllers (CCs) are used for properties like volume, panning, modulation, and pitch bend. These appear as editable curves or lines overlaid on the piano roll. Drawing in controller changes is called automation.

Working with MIDI Editors

You’ll need a MIDI controller like a keyboard or pad device plugged into your computer via a USB cable or MIDI interface to start using a MIDI editor. Your MIDI editing software needs to be set up to receive MIDI input from your controller.

Recording MIDI

To record, you arm the record function, select a track and virtual instrument, then play your MIDI controller in time with the program’s click track or metronome. The MIDI editor will display the notes you played on the piano roll.

If you make a mistake, you can either redo the recording, or go in and manually fix wrong notes using the MIDI editing tools. Quantizing can help tighten up the timing of your recorded notes. However, many people prefer to record with the quantize off, then apply it later so they can fine-tune the amount.

Editing MIDI

Most MIDI editing is done on the piano roll. You can move, lengthen, or shorten notes by dragging them. The pitch of a note can be changed by dragging it up or down to a new key on the piano keyboard graphic.

To change note velocity, you might select a group of notes and then use a scale velocity function to make them louder or softer. For smooth volume changes, you can draw in a controller curve.

Detailed MIDI editing can be time consuming, but it provides a huge amount of control. You can tweak the timing, velocity and articulation of every single note if you want. Functions like quantize, transpose, and fixed velocity make it faster to edit a lot of notes at once.

MIDI Workflow Tips

  • Use a good quality, velocity-sensitive MIDI controller for more expressive recordings
  • Aim for clean recordings with good timing and dynamics to minimize the need for editing
  • Learn the keyboard shortcuts to speed up your editing workflow
  • Name your tracks, color code them, and arrange them in folders to stay organized
  • Save different versions of your MIDI sequences in case you want to go back to an earlier edit
  • Convert your finished MIDI tracks to audio if your computer has trouble playing a lot of virtual instruments at once

MIDI Editing vs. Audio Editing

MIDI editing is very different from audio editing. Audio editors work with waveforms – visual representations of recorded sound. MIDI contains no actual audio data, only the instructions to play back notes.

Audio editing involves processes like cutting, splicing, fading, and effects processing. These permanently change the sound file. MIDI editing involves changing the notes, timing, and properties in a MIDI performance, more like a musical score.

MIDI is more flexible than audio because you can change many aspects of the notes after they’ve been recorded. With audio, you can process the sound but you generally can’t change the notes.

However, MIDI has some limitations. Since it doesn’t contain real audio, the realism and expressiveness of the sound depends on the quality of the virtual instruments. MIDI also can’t capture the subtle nuances and imperfections of a human musical performance the way an audio recording does.

In modern music production, MIDI and audio are often used together. MIDI lets you create and edit backing tracks efficiently. Recorded audio captures vocals and acoustic instruments with realism. Many songs combine MIDI instruments and loops with audio tracks.

Final Thoughts

MIDI editing is a powerful way to create and manipulate musical performances inside a computer. You can compose and arrange music without being a virtuoso player by editing MIDI notes and data directly. MIDI editing is a key part of modern music production and is used extensively in many genres. Using a MIDI editor can open up new creative possibilities and help bring your musical ideas to life.

Munyaradzi Mafaro is a music enthusiast and he also likes to tackle topics of business, productivity, and the possibilities for growth in the digital world.