Understanding MIDI

Before looking at how ChordWalk works with DAWs, SF2 Sound Samples, synthesisers, and other MIDI-enabled playing devices, it’s helpful to understand what MIDI is and how it works in music creation.

What Is MIDI?

MIDI (Musical Instrument Digital Interface) is a digital language used by music software and hardware to communicate musical information.
Importantly, MIDI does not transmit audio. Instead, it sends instructions such as:

  • Which note to play

  • When to play it

  • How long to hold it

  • How hard it is played (velocity)

  • Control changes such as modulation or expression

The sound itself is produced by the instrument or software that receives the MIDI data.

Why MIDI Is Powerful

Because MIDI only sends instructions, one application can control many different instrument sounds.

Using MIDI, ChordWalk allows you to:

  • Create rhythm, melody, and harmony

  • Play multiple virtual instruments at the same time

  • Use popular DAWs, built-in SF2 Sound Samples, or external synthesisers

  • Change instruments without changing the musical data

This makes MIDI extremely flexible for composing, arranging, and performing music.


MIDI Channels:
Keeping Everything Organised

Why MIDI Channels Exist

In a basic MIDI setup, all MIDI-enabled devices that are listening will receive the same MIDI data.
To allow different musical parts to control different instruments independently, MIDI Channels were introduced.

A single MIDI connection (or port) supports 16 independent MIDI channels.
Each channel acts like a separate lane for musical instructions.

By assigning:

  • A MIDI source (such as ChordWalk) to a specific channel

  • A receiving instrument to listen only to that channel

you can ensure that each instrument plays only the part intended for it.


Using MIDI Channels with ChordWalk

ChordWalk can route MIDI data created in any Creation Area and send it on any of the 16 MIDI channels available on a MIDI port.

This allows you to:

  • Pair individual MIDI streams with specific virtual instrument tracks in a DAW

  • Send different musical parts to multiple SF2 sound samples at the same time

  • Control several independent sounds on a multitimbral synthesiser

Each instrument listens only to its assigned channel, keeping all musical parts separate and organised.


Multitimbral Devices and General MIDI

Multitimbral Explained

A multitimbral device can play multiple different sounds at the same time, with each sound responding to a different MIDI channel.

For example:

  • Channel 1: Piano

  • Channel 2: Strings

  • Channel 3: Bass

All sounds play simultaneously from one device.

General MIDI Convention

In the General MIDI standard:

  • Channels 1–9 and 11–16 play standard instrument sounds

  • Channel 10 is reserved for percussion

    • Each note triggers a different drum sound


MIDI Ports, Virtual Ports, and Polyphony

MIDI Ports

MIDI channels operate within MIDI ports:

  • Each MIDI port supports 16 channels

  • Ports act as entry and exit points for MIDI data

You can create multiple virtual MIDI ports using tools such as LoopMIDI, giving you additional sets of 16 channels per port.
This is especially useful when running ChordWalk and a DAW on the same computer.
The ChordWalk Creator’s Guide explains how to set this up.

Polyphony

Polyphony refers to how many notes a device can play at the same time.

  • 32-note polyphony → up to 32 simultaneous notes

  • 64-note polyphony → up to 64 simultaneous notes

Polyphony affects how complex your music can be before notes begin to drop out.


Summary

  • MIDI is a language for musical instructions, not audio

  • MIDI channels allow multiple instruments to be controlled independently

  • Each MIDI port supports 16 channels

  • Multitimbral devices play multiple sounds using different channels

  • Polyphony determines how many notes can sound at once

  • ChordWalk uses MIDI channels to route musical parts cleanly and predictably

Understanding these basics will make it much easier to see how ChordWalk integrates with DAWs, sound libraries, synthesisers, and MIDI-enabled devices in the sections that follow.

Previous
Previous

Selecting MIDI Play Devices

Next
Next

Basic Overview of MIDI Channels