What is a MIDI file ?

The genetic code of music


A MIDI file is a type of file that stores digital sheet music. It contains information about which notes are played, when they are played, and how long they are played, but does not store any actual audio data. Instead, it uses a series of messages to control MIDI-enabled devices, such as synthesizers or sound modules, to generate the desired sound.


MIDI files can be played back using a variety of software and hardware devices, and can also be edited and manipulated to change the tempo, pitch, or instrumentation of a piece of music.


It is a file format that stores music-related data, such as notes, control signals, and timing information. MIDI stands for Musical Instrument Digital Interface and is a standard protocol used for communication between electronic musical instruments, computers, and other devices.


MIDI files are often used in music production and can be played back on a wide range of devices, including computer software, digital keyboards, and other electronic instruments. They can also be used to control and synchronize other devices, such as lighting and video systems.


Structure and Information FlowOverview

MIDI Files: Structure and Information Flow Overview


The information contained in a MIDI file (or MIDI sequence) is transmitted:


FROM: A transmitter (software/sequencer/DAW, keyboard, pad controller, etc.)

TO: A sound generator (sound module, VST/AU plugin, expander, MIDI synthesizer) or any MIDI device that needs synchronization


Information Contained in MIDI Files


1. Who is Playing? (Channel Information)


MIDI supports 16 distinct channels (1-16)

Each channel can represent a different instrument or sound source

Channel assignments allow multiple instruments to be controlled simultaneously


2. At What Tempo? (Timing Information)


Tempo markers specify beats per minute (BPM)

Time signature information (4/4, 3/4, etc.)

MIDI clock signals for synchronization between devices

Timing resolution (ticks per quarter note)


3. With Which Sound? (Program/Patch Information)


Program Change messages to select specific sounds/patches

Bank Select messages to access extended sound libraries

General MIDI (GM) standardized program numbers for common instruments

Sound parameter controls via Control Change messages


4. When? (Event Timing)


Absolute time positions for each event

Quantization information (how strictly events align to the grid)

SMPTE time code for synchronization with video/external devices

Markers and cue points for navigation


5. With Which Notes and How? (Note Information)


Note number (pitch from 0-127, where 60 = middle C)

Velocity data (how hard a note is struck, from 1-127)

Articulation information via Control Change messages

Pitch bend data for expressive pitch variations


6. For How Long? (Duration Information)


Note-On and Note-Off events define duration

Sustain pedal information

Release velocity (how quickly a key is released)

Legato and staccato indications


7. Additional Control Options


Modulation wheel data

Expression controls

Effects parameters (reverb, chorus, etc.)

Aftertouch (pressure applied after striking a key)

System Exclusive (SysEx) messages for device-specific functions

Controller automation data

MIDI Machine Control (MMC) for transport functions

MIDI Show Control (MSC) for theatrical applications

Mixer automation data (volume, pan, etc.)

Loop points and repeat instructions


MIDI files serve as a compact and versatile format for storing musical performance data without the audio itself, making them ideal for editing, arranging, and transferring musical ideas between different systems and devices.

How are they interpreted?

It is simply a sequence of instructions that run line by line in all dedicated software and hardware: Cubase, Logic, Live!, Korg, Yamaha, Roland, Arturia, Musescore, Reason, GuitarPro, Adobe etc. Thousands of pieces of information can be listed, from the note, to volume and velocity indications, and even more "complex" parameters such as effect settings, or specific to the hardware you are using.

Laurent WALKER-HAVETTE

Musician & founder

SYNTH-SATIONAL CONFESSIONS OF A KEYBOARD ADDICT! 🎹⚡CATS KNOW BEST! 😺🎹

OMG, I've been TOTALLY BEWITCHED by these electronic noise-makers ever since those ear-candy hooks in Eurythmics' "Sweet Dreams" (1983) and pretty much EVERYTHING Vince Clarke has touched (Depeche Mode, Yazoo, Erasure)! 🤩

Why am I so obsessed? Probably because synthesizers are basically WIZARDRY IN A BOX—they've tamed electricity and turned it into INFINITE sound worlds! And honestly? I don't want anyone explaining the technical mumbo-jumbo behind it all. NOPE! Let that synth magic stay mysterious, thank you very much! ✨🔮

Fun fact: I started making music the EXACT SAME YEAR that MIDI was born (talk about destiny, right?!). Since then, I've gotten my fingers on SO MANY keyboards! And let me tell you—it's not just about the sounds they make. The interfaces, the feel of the keys, and YES, even how they SMELL have all shaped my musical creations and the different setups I've cobbled together over the years.

Each synth is like a quirky friend with its own personality... just with more blinking lights and fewer opinions about my fashion choices! 🎛️🎚️