MIDI in music production: understanding the digital protocol powering professional and home studios.


Before jumping into music production, it's extremely important to learn some basics first. In my experience, understanding MIDI is often the first challenge for people new to this, especially musicians who are used to playing physical instruments and may not be tech-savvy. The idea that MIDI is just digital data representing a musical composition, without containing actual sounds, can be confusing at first. This article is about what MIDI is and how it technically works. Grasping concepts like MIDI, digital music, and how it gets converted into analog waveforms may sound boring, but it's crucial knowledge for music producers. It allows you to better understand the digital music processes within your digital audio workstation (DAW). Having a handle on some MIDI theory goes a long way in demystifying your DAW and setting you up for success in music production. It may feel tedious at first, but stick with it! Once you've got the basics down, it gets much smoother.


The following diagram illustrates the different types of signal interaction between devices



What is MIDI?


MIDI is a language that simply conveys information about which note was played, the intensity of the keypress, and the duration of the note. It is not audio, computers can read this MIDI language and convert it into sound using their built-in sound libraries.

MIDI (Musical Instrument Digital Interface) is a technical standard that allows electronic musical instruments, computers, and other equipment to connect with each other and exchange musical performance data. The MIDI protocol transmits event messages that specify notation, pitch, velocity, vibrato, panning, cues, and clock signals. This allows sequencing, automation, and remote performance control of musical instruments from a computer or other device.


The key elements of MIDI data include:


  • Note On/Off Messages – Triggers a note to start or stop. Includes pitch and velocity.
  • Control Change Messages – Alters parameters like volume, panning, vibrato, and sustain.
  • Program Change Messages – Selects instrument sound patches.
  • Pitch Bend Messages – Bends note pitch up and down.
  • System Exclusive Messages – Allows custom controller data.
  • System Messages – Tempo, time signature, song position, etc.

Because MIDI files contain no actual audio data, they are very small in file size. This allows MIDI sequences to be transferred between devices nearly instantly. The performance information can then be interpreted into audio on the receiving end. This is what makes MIDI so versatile for music production and performance applications.



How MIDI Works


MIDI messages communicate musical performance data between devices. For example, when you play a key on a MIDI keyboard, it sends a MIDI note-on message with a pitch value that corresponds to that key. This pitch value is encoded numerically between 0-127, where 60 represents middle C. The velocity, or how hard the key was struck, is also encoded from 1 (soft) to 127 (hard). When the key is released, a note-off message is sent. These messages allow MIDI devices to exchange musical performance information in a standardized way.

Messages are sent over 16 MIDI channels, which allows connecting multiple instruments and separating their signals. For example, channel 1 could be assigned to a bass sound, channel 2 to drums, etc. MIDI channels allow each device to receive only the messages relevant to generating its sound.

In addition to note on/off messages, MIDI can transmit controller data like sustain pedal, modulation wheel, and pitch bend values. This continuous controller data allows more expressive performances. MIDI can also synchronize tempo via clock messages, which is vital for lining up sequenced parts between instruments.

MIDI messages are sent at a high rate to capture the nuances of a performance. At a 10 ms interval, this produces 100 messages per second. MIDI data has a very small bandwidth of only 31.25 kbps. This allows MIDI to be transmitted over simple cables up to 15 meters long. Opto-isolators keep MIDI devices electrically separated, avoiding ground loops while maintaining fast transmission speeds.

While MIDI transmits performance data, it does not transmit an audio signal. The receiving instrument is responsible for generating audio based on the MIDI messages using oscillators, samplers, or other sound sources. This is a key distinction between MIDI and digital audio.


How Is MIDI Used in Music Production?


In a typical home studio setup, a MIDI controller like a keyboard is connected to a computer running a digital audio workstation (DAW) like Ableton Live, Logic Pro, Pro Tools, or FL Studio. 

Within the DAW software, the MIDI data generated from the controller can be routed to trigger sounds from virtual instrument plugins like synthesizers, samplers, and drum machines.

Here are some of the most common ways MIDI is leveraged in modern music production:

  • Playing software instruments like piano VSTs, synth VSTs, and drum VSTs using MIDI controllers.
  • Drawing in MIDI note patterns with your mouse to program melodies, baselines, and drum beats.
  • Importing MIDI loops and phrases to quickly add musical elements like arpeggios, fills, etc.
  • Editing MIDI note pitch, length, velocity, and other parameters from recorded performances.
  • Using MIDI effects plugins like arpeggiators, chord generators, etc.
  • Automating parameters like volume, panning, and filter cutoff for dynamic sound design.
  • Synchronizing equipment like drum machines and hardware synths via MIDI clock.

The power of MIDI in production is that it can be used to compose, manipulate, and perform musical parts in extremely flexible ways. MIDI data functions as a universal language between music devices and software.


Types of MIDI Controller Hardware


To take full advantage of MIDI when producing music on a computer, you need the right MIDI controller hardware. Here are some of the most common types:

  • MIDI Keyboard – The main way to play melodic instruments, basslines, and harmonies. Keys with velocity/pressure sensitivity provide more expression.
  • MIDI Pads – Used for programming drums/beats or performing chromatic samples and clips. Look for velocity/pressure sensitivity.  
  • MIDI Faders and Knobs – Assign these to control DAW, virtual instruments, and effects parameters for easier automation.
  • MIDI Pedal – A sustain pedal allows prolonging notes on compatible instruments like piano VSTs.
  • MIDI Breath Controller – For adding natural expressiveness when playing wind/brass instruments.
  • MIDI Drum Kits – Play electronic drum sounds using realistic pads and cymbals.

Many all-in-one controllers combine multiple elements like keys, pads, and knobs for flexible hands-on control. Look for MIDI hardware that integrates tightly with your DAW and instruments.


MIDI Controller Keyboards


Dedicated MIDI controller keyboards and pads are the most common way of playing and recording MIDI performances. These controllers do not produce sound themselves but instead send MIDI messages to external tone generators. Controller keyboards provide a piano-style interface ideal for entering melodic parts. pad controllers like the Akai MPD line are great for playing drum parts and rhythmic sequencing.

MIDI controllers come in a variety of sizes from 25 keys up to full 88-key keyboards. The keys themselves don't move but instead, sense pressure and send velocity values. Most keyboards offer assignable knobs, sliders, and buttons to control DAW and synth parameters. High-end controllers feel extremely realistic and responsive due to advances in keybed and sensor technology.

Wireless MIDI controllers allow more freedom of movement and distance from the computer. Many keyboards have built-in MIDI to USB connectivity for plug-and-play use with recording software. iOS devices and Web apps utilize MIDI over Bluetooth LE and other wireless protocols. This allows mobile music production and controller. 


MIDI Outboard Equipment


Electronic drum kits also utilize MIDI trigger pads and controllers. Drum machines like the legendary Roland TR-808 were early adopters of MIDI implementation. Guitar controllers with MIDI pickups can convert guitar playing into MIDI data. There are even MIDI controllers for wind and string instruments. Almost any instrument can be adapted to communicate via MIDI messages.

On the receiving end, hardware sound modules and rack synths contain preset or customizable sounds that respond to the MIDI data by generating audio. MIDI instrument and patch data can be saved for future use. Advanced MIDI instruments allow tweaking filters, envelopes, and other parameters for custom sound design.

Sequencers and recording equipment utilize MIDI for capturing and playing back performances. Traditional analog sequencers have been replaced by MIDI sequencing software on computers. Recording studios integrate MIDI with other instruments and vocals during production. MIDI data can be edited with great flexibility compared to recording audio.



MIDI Software


Computer software plays an essential role in the modern use of MIDI. Sequencing programs like Ableton Live, Logic Pro, and FL Studio allow recording, editing, and playback of MIDI sequences. The MIDI data can be entered in real-time with a MIDI controller or programmed and quantized into the sequencer.

Softsynths (software synthesizers) generate audio from the MIDI performance messages in real time. Popular software instrument plug-ins include Native Instruments Massive, u-he Diva, Xfer Serum, and many others. The expressive capabilities of these software instruments rival their physical counterparts while offering limitless sound design options.

Digital audio workstations (DAWs) combine sequencing, MIDI editing, and softsynths in an integrated production environment. DAWs provide tools for composing, recording, editing, mixing and mastering music from MIDI parts all the way to commercial release.


MIDI Packs


MIDI packs are collections of MIDI files containing compositional data and rhythmical data for producers to use in their music productions. They can contain melodies, chord progressions, basslines, and drum patterns programmed as MIDI data. They often come genre-specific, like MIDI packs for hip hop, EDM, pop, etc.

MIDI packs can simply be imported directly into a DAW and provide building blocks that producers can use to quickly add musical ideas, harmony, and rhythmic structure. Transmission samples MIDI packs are royalty-free or come with a license allowing commercial usage. Using high-quality MIDI loops and phrases can help speed up the music production workflow. Combining and manipulating the MIDI data allows endless creativity. At transmission samples, we have a huge selection of MIDI packs, including Trance MIDI compositions and products that contain both audio and MIDI composition data such as this Ambient MID pack.


Creative Sound Design Using MIDI


One powerful advantage of software instruments over traditional hardware is the ability to customize and shape your own sounds. Using MIDI and synthesizers, you can sculpt sounds from scratch through additive synthesis, filtering, modulation, and effects processing.

MIDI’s precision control and automation capacity expands your creative options exponentially for crafting unique electronic tones tailored precisely to your track. The tactile control surface of MIDI controllers combined with the tweakability of soft synths opens new sound design possibilities.

Some effective techniques for designing original sounds with MIDI:

  • Tweak synth parameters using MIDI continuous control messages or by mapping knobs to alter the sound in real time.
  • Sequence filter cutoff, resonance, or other parameters using MIDI modulation data for dynamic motion.
  • Use pitch bend and mod wheel messaging to add expressive vibrato and resonance.
  • Automate filter types, attack, delay times, etc. on synth layers to evolve the sound over time. 
  • Layer instruments, then offset the MIDI note start times and alter individual parameters for each layer.
  • Use MIDI velocity data to trigger different oscillator waveforms or filter settings on each note.

If you can conceive a sound in your imagination, there’s likely a way to create it using MIDI and virtual instruments. The creative potential is limitless.


MIDI Clock Sync and Tempo


An important MIDI capability is the ability to synchronize hardware instruments and devices to a central tempo and clock. DAWs can transmit MIDI clock data in real time to drum machines, synthesizers, and other gear. This ensures everything stays in perfect sync even when adjusting the master tempo.

Some examples of using MIDI sync:

  • Keeping an analog synth or drum machine locked to your DAW’s tempo during recording.
  • Syncing up multiple hardware drum machines playing together.
  • Using MIDI to sync effects like delay to your master time signature.

MIDI clock is an invaluable tool for producers incorporating hardware instruments into computer-based studios. Everything can evolve together at the same BPM.


MIDI Show Control

MIDI Show Control is an advanced implementation allowing complex real-time synchronization and automation between MIDI devices and software. It is used widely in live performances and theater shows.

Some examples include:

  • Triggering lighting cues from MIDI notes.
  • Synchronizing visuals/projections to musical performances.
  • Changing synthesizer patches in time throughout the track.
  • Executing choreographed stage instrumentation.

While less applicable in the studio, understanding MIDI Show Control unlocks creative live performance and choreography potential.


The Future of MIDI


After over 35 years, MIDI remains ubiquitous in music gear from portable production rigs to full-scale studio complexes. The simple and efficient protocol has undergone incremental improvements but remains compatible with nearly all legacy MIDI devices. An updated MIDI 2.0 specification adds extended functionality for more complex control messages while retaining backward compatibility.

MIDI forms the backbone of music-making from top charts to bedroom productions. New instruments, controllers, hardware, and software continue to adopt MIDI implementation. Seamless integration between digital devices has kept MIDI relevant while audio, sequencing, and music production technology has transformed around it. Far from disappearing, MIDI's role in modern music creation and performance continues to expand. From electronic dance anthems to ambient synth soundscapes, MIDI delivers the foundation of musical data essential to realize any digital vision or inspiration.


Conclusion


Whether you produce hip-hop, pop, EDM, or any other contemporary genre, learning how to use MIDI in music production is essential. MIDI empowers producers, composers, and performers to make music free from physical limitations and to control gear with precision.

Understanding MIDI opens creative gateways to customize sounds, improve playing technique, synchronize equipment, and produce visually synced performances. Immerse yourself in the capabilities of MIDI and prepare to bring your productions to the next level.


Topic Description
What is MIDI? MIDI (Musical Instrument Digital Interface) is a protocol that allows digital musical instruments, computers, and other equipment to communicate and exchange data for controlling musical performance parameters.
How MIDI Works MIDI transmits event messages like note on/off, pitch, velocity, control changes, program changes, etc. This data is sent over 16 channels which allows connecting multiple instruments and separating their signals.
MIDI Hardware Common MIDI instruments include controller keyboards, electronic drum pads, guitar controllers, etc. MIDI sound modules and synths generate audio from the MIDI data. Sequencers and recording devices capture MIDI performances.
MIDI Software Sequencing, notation, virtual instrument, and DAW software allow recording, editing, and playing back MIDI sequences to control softsynths, effects, and parameters.
MIDI Controllers Keyboards, pads, faders, knobs and pedals are used to generate and manipulate MIDI control messages to shape sound and performance attributes.
MIDI Sync MIDI clock allows synchronizing tempo, time signature, and sequences between multiple hardware devices and computer software.
Sound Design MIDI facilitates extensive real-time sound manipulation and automation for custom sound design during music production.
The Future of MIDI After 35+ years, MIDI remains essential to digital music workflows. The simple, flexible protocol continues to adapt to new technologies while retaining backward compatibility.