On this page we will look at computer software applications that use
MIDI. This page in no way encompasses the vast use of MIDI in computer programs.
Included are examples of some programs that demonstrate the wide variety
of uses with the MIDI specification. Different types of software include:
When you first glance at an interface of a MIDI sequencer, it has
the similar look of a tape recorder. You have the typical transport controls
as well as tracks of music information. The big difference is the actual
information that is recorded. With an analog tape recorder the acoustic
waveform is recorded on a magnetic tape. With a digital tape recorder digital
numbers are recorded to represent the acoustic signal. A MIDI sequencer
records MIDI events. There are MIDI sequencers that also have the capability
of recording digital audio and they will be discussed later.
The diagram below displays eight MIDI tracks of information with each
track sending notes, program changes, controller parameters to the individual
instruments. The sequencer does not playback the actual sounds, but sends
MIDI information to the synthesizers that generate the sounds. Once the
MIDI information is stored in a sequencer there are many ways to manipulate
the data. The diagram below is an overview, but the user can get a more
detailed look at the information by clicking on certain icons.
Another attractive feature of a MIDI sequencer is the ability to
add control changes after the recording. In the example to the left the
key velocity for each note is represented in a graph. The user may change
the velocities with the stroke of a pencil using a mouse. Other control
options include program changes, pitch bend, fader controls, modulation
wheel, panning, and many more.
Piano roll editing and graphic editing is one way to manipulate the MIDI
data. It is possible to view the same information in notation form or in
an event listing.
To the right is an example of an event listing of note information.
Here the notes are listed with their location in each measure as well as
position in absolute time.
MIDI sequencers include timing information on the tempo of the composition.
MIDI events may be recorded at a slow tempo and then played back at a faster
speed. To get a better understanding of time and tempo features I recommend
MIDI Timing Concepts
Another important feature of MIDI sequencers is the input options. Advanced
sequencers will give the user three options for inputting data.
Real Time Recording - Incoming data is recorded as the performer
plays on a MIDI controller.
Step Time Recording - Allows the performer to input notes of events
one step at a time from the controller, or with the computer keyboard or
Loop Recording - Allows the user to decide on a specific amount
of measures with a repeat mode to enter data. It is very similar to a drum
machine tap mode.
So far this demonstration has centered on Computer Based
MIDI sequencers (right image). Other types of MIDI sequencers include:
Dedicated Sequencers - are multi-track recorders of MIDI digital
information. They are called dedicated because their only
function is to record MIDI information. An excellent choice for a sequencer
if you move your equipment around a lot for "gigs", and they usually
cost less than a computer.
Workstation, On Board Sequencers - Many work stations (synthesizers,
drum machine, sequencer), now have small sequencers built in that allow
multi-track recording of MIDI information.
A powerful combination is MIDI sequencing and digital audio. This
allows the user to have MIDI files playing synthesizers in sync with digital
audio tracks. The programs are more expensive than a MIDI sequencer and
the computer need to have fast microprocessors as well as large amounts
of memory to store the digital files.
To the right and below are examples from the program ProTools by digidesign.
Highlighted in yellow are digital audio tracks as well as MIDI tracks.
to the menu
There is usually a graphic interface that gives the user many options
on note and rest values as well as musical marking symbols, text, musical
Files may be saved as a document file or exported as a Standard MIDI
file that could then be read by another notation program or a MIDI sequencer
program. Some programs will allow the user to create a full score of a composition
as well as extracting the individual parts with transposition for individual
instruments. The graphic interface is usually very intuitive and in little
time a composition can appear as a professional copy.
Computer programs that involve music instruction have advanced to new
levels in recent years. There are four main categories of software and the
range is from the very beginning user to the advanced user. The categories
The programs that are listed below have MIDI capabilities. There are
many excellent CAI music programs that do not use MIDI, but they are not
discussed on this page. I recommend the book Experiencing
MUSIC TECHNOLOGY for a complete review of CAI music software programs.
The programs that are described here are applications that deal with
MIDI. There are many Sound Editing Programs that work with digital audio
sound files. Examples would include Sound Edit 16, Alchemy, Sound Designer,
and Pro Tools. These programs allow the user to manipulate sound file samples,
but they do not use MIDI techniques to edit the sound file.
Music Patch Editors work directly with the sound patches within
a synthesizer. Patch editors are designed specifically for individual synthesizers
because each company uses their own system exclusive information
to create their programs. First the hexadecimal code F0 is used to identify
the status byte of system exclusive. The status byte is followed by a data
byte that identifies the manufacturer. All data bytes that follow pertain
to MIDI information created by that particular manufacturer. At the end
of the system exclusive message will be the hexadecimal code F7 end of exclusive
Patch Editors allow the user to change the size of envelopes, types of
filters, samples, waveforms, panning information, modulation effects and
basically anything that changes the parameters of the patch. Each manufacturer
uses different techniques to create sounds for the synthesizer so each Patch
Editor must be designed for the specific synthesizer. Universal Patch
Editors are programs that support many different MIDI devices. That
way a user may by one program that will support their studio that has products
from Roland, Yamaha, Korg or other manufactures.
The example on the left is the Universal Patch Editor Galaxy. Here the
user is able to make changes to the envelopes, original oscillators, filters
and other effects.
Image from the book Experiencing MUSIC TECHNOLOGY
Sometimes a sound from one synthesizer may be layered with MIDI
to another sound in a different synthesizer to create a new combined sound.
The librarian will allow the user to move patches so the combination is
on the same number.
The computer program Max allows the musician to use a graphical
environment to represent musical events. This program allows the user to
manipulate and control MIDI events in new ways that are not limited by the
conventions of a music sequencer or notation software.
The program can send MIDI event information to synthesizers as well as
performance event information to a compact disc or CD-ROM.
MIDI takes up less space than digital audio files which makes it a valuable
option in many Multimedia programs. Some p